Causes:

• Urinary Tract Infection (UTI) or bladder infections (cystitis)
• Canine hepatitis
• Coccidiosis

Urinary Tract Infection (UTI) or bladder infections (cystitis) may cause lower abdominal tenderness as bacteria in the urethra or urinary bladder create inflammation. A severe case of canine hepatitis could also cause abdominal tenderness and the abdominal tenderness may be accompanied by other symptoms such as bloody diarrhea, coughing and increased thirst and urination. Coccidiosis, a protozoan parasite disease common in puppies, may also cause abdominal tenderness. The parasites reproduce in the intestinal tract and may result in intestinal dysfunction that causes abdominal tenderness as well as watery and/or bloody diarrhea.

Aggression toward people and animals

• Hypothyroidism
• Hypoglycemia
• Brain inflammation

Aggression in dogs in the form of growling, showing teeth, snapping and/or displaying a dominant posture may be caused by various medical conditions. Hypothyroidism, a common disease of the endocrine system, can cause aggression in dogs as abnormally low thyroid levels can drastically affect mood. Besides aggression toward people and animals, dogs with hypothyroidism may also exhibit excessive hair loss, weight gain and/or lethargy. Hypoglycemia, or low blood sugar, may also cause aggression in dogs as low blood sugar levels may cause dogs to feel a sense of weakness and disorientation. Brain inflammation from diseases such as distemper, meningitis and many others, can also cause dogs to feel aggression toward people and animals due to neurological reactions to the inflammation.

Avoidance of water:

Causes:

• Aging
• Vasoconstriction reaction to cold weather
• Cancer

Avoidance of water due to decreased thirst is fairly common in older dogs. Older dogs may display an avoidance of water due to less activity and longer periods of rest. Dogs of all ages may display an avoidance of water in cold temperatures due to vasoconstriction. Vasoconstriction is the body’s way of minimizing heat loss by decreasing blood flow. The hormones that signal the kidneys to conserve liquid in normal blood flow may not be detected during vasoconstriction and a decreased sensation of thirst that causes an avoidance of water may result. Cancer can sometimes be a cause of an avoidance of water in dogs, depending on the organs involved, as cancer may interfere with thirst and appetite sensations.

Bright red blood in the stools (Hematochezia):

• Parasites
• Alergic reaction
• Diseases of the colon, anus or rectum

• Bleeding ulcers
• Parasites
• Diseases of the stomach, intestine, liver or pancreas

Parasitic infections may irritate and cause bright red blood from the gastrointestinal tract in the lower intestines/digestive system or black blood from the gastrointestinal tract in the upper intestines/digestive system. An allergic reaction to food or medicine may also cause bright red bleeding from the gastrointestinal tract due to digestive upset. Bleeding ulcers in the stomach, esophagus and small intestine are a fairly common cause of bleeding from the gastrointestinal tract and may result in black stools. Digestive tract diseases may also cause bleeding from the gastrointestinal tract due to irritation or inflammation. If a dog swallows blood, the ingested blood may also cause black stools.

Bleeding from the nose and gums

Causes:

• Cancer
• Von Willebrand disease
• Rat poison

Oral and nasal cancer may cause bleeding from the nose and gums due to malignant swelling from a cancerous mass. Swelling of the face and labored breathing often accompany bleeding from the nose and gums in cases of canine nasal and oral cancer. Von Willebrand disease, an inherited blood disorder, causes bleeding from the nose and gums, as well as other areas, as the disease does not allow proper blood clotting. Bleeding from the nose and gums is often first noticed in teething puppies with Von Willebrand disease. Contact with rat poison could also cause bleeding from the nose and gums as the chemicals in rat poison usually impair blood clotting ability.

Bleeding under the skin

Causes:

• Hemophilia
• Tick-related diseases
• Traumatic injuries

Hemophilia, an inherited blood disorder, may cause bleeding under the skin as the disease prevents normal blood clotting ability. Bleeding under the skin may be the first sign of hemophilia in puppies, along with profuse bleeding after losing baby teeth. Tick-related diseases such as Lyme disease and Rocky Mountain Spotted Fever may also cause bleeding under the skin due to the irritation caused by the infestation of the parasitic ticks. Fever, swollen joints and loss of appetite may also be present with bleeding under the skin in dogs with tick-related diseases. Traumatic injuries to the skin such as those experienced from a fall can cause bleeding under the skin that presents as bruising.

Bloody diarrhea

Causes:

• Hookworms
• Whipworms
• Hemorrhagic Gastroenteritis (HGE)

Hookworms may cause bloody diarrhea in dogs as the worms feed on blood in the small intestine and the bleeding continues after the worms leave the feeding spot. Weakness and weight loss may accompany bloody diarrhea when a hookworm infestation is present. Whipworms may also cause bloody diarrhea due to the intestinal inflammation they can produce in the large intestine. Hemorrhagic Gastroenteritis (HGE) may cause a sudden case of bloody diarrhea. The bloody diarrhea may be accompanied by other symptoms such as loss of appetite, lethargy and vomiting.

Coughing (persistent)

Causes:

• Canine influenza virus
• Collapsed trachea
• Canine distemper

The canine influenza virus is a fairly new disease that often causes persistent coughing as it has a pneumonia-like affect on the respiratory system. The canine influenza virus is not the same as the parainfluenza virus and yellow discharge from the nose may accompany the persistent coughing. A collapsed trachea may also cause persistent coughing because the damaged trachea, or windpipe, can not bring the normal amount of air into the respiratory tract. Canine distemper, a contagious viral disease, can be another cause of dry, persistent coughing as it affects the respiratory system as well as the nervous and gastrointestinal systems. Besides the persistent coughing, vomiting, seizures, diarrhea, fever and loss of appetite can occur in canine distemper cases.

Coughing (occasional):

Causes:

• Normal clearing of airways
• Heartworm
• Heart disease

The normal clearing of airways may cause occasional coughing in dogs as occasional coughing is a natural way of clearing breathing passages such as when food or drink goes down the ‘wrong pipe’. Occasional coughing may also be an early sign of heartworm as heartworm affects the lungs. Exercise intolerance may accompany occasional coughing in heartworm cases. Heart disease may also include occasional coughing as a symptom due to its affect on the lungs and respiratory system.

Coughing (unproductive, or dry):

Causes:

• Bordetella
• Parainfluenza virus
• Canine distemper

The bacterial infection bordetella is a common cause of unproductive or dry coughing and is associated with “kennel cough” – a canine bronchitis. The parainfluenza virus, not to be confused with the canine influenza virus, can also cause very unproductive or dry coughing as it can have a severe affect on the respiratory system. A loss of appetite and discharge from the eyes and nose may accompany the unproductive or dry coughing in parainfluenza cases. Unproductive or dry coughing is also an early sign of canine distemper. Besides unproductive or dry coughing, symptoms of canine distemper may include diarrhea, fever, vomiting, seizures and loss of appetite.

Crying out when moving:

Causes:

• Cruciate ligament injuries (knee injuries)
• Canine hip dysplasia
• Osteochondritis Dissecans (OCD) (also called Osteochondrosis Dissecans)

Cruciate ligament injuries are knee injuries that may cause crying out when moving as the dog’s knee joint may twist and cause pain when the dog runs or jumps. Canine hip dysplasia, a genetic disease involving hip joint damage, may cause crying out when moving due to the pain caused by a loose hip joint and/or inflammation caused by arthritis. Osteochondritis Dissecans (OCD) involves abnormal bone cartiladge and may cause crying out when moving because of the pain caused by parts of bone cartiladge that may snap off. Severe crying out when moving may occur if the snapped-off cartiladge grows larger as it moves freely in the joint. Crying out when moving may also be accompanied by a dog’s reluctance to move or jump in any painful condition that affects the bones or joints.

• Bacterial organisms or intestinal parasites
• Ingested substances such as garbage or allergens
• Extraintestinal diseases such as Addison’s disease, intestinal cancer or
  Inflammatory Bowel Disease (IBD)

Bacterial organisms and intestinal parasites are common causes of diarrhea in dogs. Bacteria and parasites that cause diarrhea may be ingested by dogs such as in rotten meat from the garbage can. Bacteria and parasites often cause diarrhea by irritating the digestive tract. Allergens or foreign objects such as toys that the dog swallows may also cause digestive upset and diarrhea. Many different extraintestinal diseases may also cause diarrhea depending on the organs involved.

• Parasitical infections
• Bacterial infections
• Yeast infections

Infections from parasites such as ear mites can cause a dark, powdery brown discharge from the ears with an excessive amount of ear wax. The ear mites can be observed in the discharge from the ears when the discharge is viewed under a microscope. Bacteria may also cause discharge from the ears and the discharge is often yellow and pus-like, due to the irritation and infection from the bacteria. Yeast infections may cause a brown, wax-like discharge from the ears. Shaking the head, scratching the ears and discharge from the ears that may be foul-smelling is common in all types of canine ear infections due to inflammation, infection and irritation of the external ear canal.

• Allergies
• Eye infections
• Entropion

Clear discharge from the eyes is usually normal, but an excess of clear discharge from the eyes may signal allergies. Sometimes, scratching and rubbing of the face and reddening of the eyes may accompany clear discharge from the eyes when an allergy is present, due to the irritation caused by the allergen. Eye infections may cause a yellow, green or gray discharge from the eyes due to a virus. Entropion, a genetic disorder, may also cause discharge from the eyes because the eyelashes face inward rather than outward and irritate and/or infect the eye’s surface.

• Colds or allergies
• Infection
• Cleft palate or palate injury

Colds and allergies can cause thin, clear discharge from the nose in dogs just as they do in humans. A canine viral infection can cause a thick, sticky discharge from the nose, while a canine fugal or bacterial infection can cause a white discharge from the nose. Milk or food that appears in discharge from the nose suggests a hole on the roof of the dog’s mouth. Rather than the food or milk going down the dog’s throat, the hole allows some of the food or milk to exit as discharge from the nose. The hole could be caused by either a cleft palate birth defect or by damage done to the palate such as from a fall.

• Epilepsy
• Cognitive Dysfunction Syndrome (CDS)
  (also called dog Alzheimer’s)
• Hypoglycemia

Epilepsy may cause disorientation just before a seizure as the dog may feel that an epileptic attack may occur or that something is wrong. Restlessness and either hiding or trying to get the owner’s attention may accompany the epilepsy-associated disorientation. Cognitive Dysfunction Syndrome (CDS), or dog Alzheimer’s, can cause extreme disorientation such as getting lost in familiar surroundings or confusing indoors with outdoors and soiling in the house. Dogs with disorientation caused by CDS may even forget who their owner is. Hypoglycemia, or low blood sugar, may also cause disorientation due to the affect of the loss of glucose to the brain. Shivering, seizures and lethargy may also accompany disorientation in dogs suffering from hypoglycemia.

• Poison ingestion
• Gastric Dilatation Volvulus (GDV) (also called bloat)
• Infection or allergy

Swallowing poison such as bone meal fertilizer may cause dry heaves in dogs. The poison has a toxic affect on the body and the dog may react by trying to force the substance out of the body with dry heaves. Gastric Dilatation Volvulus (GDV), or bloat, is an often deadly condition in which the stomach is twisted and grows larger due to air and fluid unable to escape. The dog may engage in dry heaves to try to eliminate the pain and trapped air and fluid. An infection from an intestinal parasite may also cause dry heaves due to stomach pain and irritation. A food or other allergy that affects the gastrointestinal tract may also cause stomach pain and irritation that the dog may try to relieve through dry heaves.

• Lymphoma
• Juvenile cellulitis (also called juvenile pyoderma and puppy strangles)
• Anthrax exposure

Lymphoma, cancer of the white blood cells, causes enlarged lymph nodes in the neck due to the growth of a tumor in the white blood cells, or lymphocytes, as well as in the lymphatic tissue. Enlarged lymph nodes are often first noticed in the neck, but medical tests usually reveal enlarged lymph nodes all over the body. Juvenile cellulitis, or puppy strangles, may also cause enlarged lymph nodes in the neck as well as the head. The enlarged lymph nodes in the neck can cause labored breathing and may strangle the puppy. Coughing and gagging, diarrhea and hair loss often accompany enlarged lymph nodes in the neck in cases of juvenile cellulitis. Anthrax exposure may sometimes cause extremely enlarged lymph nodes in the neck and head because of the body’s reaction to the anthrax bacteria.

• Lyme disease
• Lymphoma
• Coccidiodomycosis (also called Valley Fever)

Lyme disease is a tick-related disease that can cause enlarged lymph nodes in the part of the body where the bacterial infection caused by the tick occurs. A low-grade fever and reluctance to move may accompany the enlarged lymph nodes. Lymphoma is cancer of the white blood cells and it can cause enlarged lymph nodes all over the body due to tumor growth in cells and tissue. Enlarged lymph nodes are frequently first discovered in the neck before medical exams discover them elsewhere. The lung infection Coccidiodomycosis, or Valley Fever, may cause enlarged lymph nodes in the shoulder blades, chin and heart areas and coughing may also occur as the enlarged lymph nodes put pressure on the windpipe.

• Dental or oral cavity disorders
• Mouth injuries
• Heat stroke

Gum disease or gum inflammation such as gingivitis may cause excessive salivation as a reaction to mouth pain. Stomatitis, the inflammation of the mucus membranes in the mouth, may also cause excessive salivation due to pain. Dogs suffering from dental or oral cavity disorders will often have a loss of appetite as well as excessive salivation. Mouth injuries such as trauma to the tongue or oral cavity from insect stings or chemical burns may also cause excessive salivation because of the brain’s reaction to pain and/or fear. Heat stroke may also trigger the reaction of excessive salivation when the body temperature begins to increase at a drastic rate.

• Obesity
• Heart disease
• Lung disease

Obesity may cause exercise intolerance as an overweight dog may not have the stamina of a fit dog to handle heavy exercise. Some dogs that suffer from obesity may have trouble just walking or moving and have extreme exercise intolerance. Heart disease is another cause of exercise intolerance as exercise can put stress on the heart and heart muscles are often weakened. Besides exercise intolerance, fainting, weight loss, panting and coughing may be other signs of heart disease in dogs. Lung disease can cause exercise intolerance due to exertion put on lungs damaged by disease, collapse or blockage.

• Heart disease and heart block
• Injuries
• Epilepsy

Heart disease is a common cause of fainting in dogs as heart problems can result in heart block. Heart block can cause an interruption in electrical signals in the heart so that the blood flow suddenly stops, and this can result in fainting. Weight loss, coughing, panting and exercise intolerance often accompany fainting in many cases of canine heart disease. Injuries such as banging the head, having an object caught in the windpipe and strong toxic fumes from pest spray or some paints can also cause fainting in dogs. Epilepsy may also cause fainting because of the interruption in brain circuitry during seizures.

• Infection or inflammation
• Cancer
• Coccidiodomycosis (also called Valley Fever)

Infection and inflammation from blood parasites may cause fever. Fever can also be caused by liver, kidney, urinary tract or heart infections. Cancer may also cause fever as well as loss of appetite and lethargy. Fever may be the first symptom of the lung disease coccidiodomycosis, or Valley Fever. Fever is often thought to be the body’s way of trying to fight off infection.

• Ear infections
• Ears or fur that covers the ear canal
• Allergies

Ear infections from parasites, bacteria and yeast may cause a foul ear odor. The foul ear odor in an ear infection is often accompanied by redness in the ears and/or crying out when the ears are touched due to pain. Floppy eared dogs such as hounds and spaniels or dogs with fur in the ear canal are more likely than dogs that have more air flow to the ears to have a foul ear odor. The covered ears can create an environment that parasites, bacteria and yeast often thrive in. Allergies can sometimes be a cause of foul ear odor. Allergies may be present if, in addition to the foul ear odor, a dog scratches the ears, licks the paws and displays weakness.

• Tracheobronchitis (also called ‘kennel cough’)
• Heart failure
• Mucus-producing conditions

Kennel cough, or tracheobronchitis, often causes gagging as well as dry coughing. Kennel cough is a contagious respiratory disease that can cause gagging from irritation on the pharynx. Heart failure can also cause gagging and coughing since blood and fluid may leak from the improperly-pumping heart into the lungs. The worse the condition of the heart, the more fluid can leak out and the stronger the gagging. Mucus-producing conditions such as allergies, viral infections, throat cancer or problems with the esophagus can also cause gagging in dogs.

• Flea-associated dermatitis
• Canine atophy
• Pyotraumatic dermatitis (also called ‘hot spots’)

Flea-associated dermatitis can cause hair loss, especially near the base of the tail and in the toe webs. Canine atophy, a genetic disease, may also cause hair loss. Canine atophy predisposes a dog to allergies and allergies can cause skin problems in dogs that lead to scratching and rubbing which can lead to hair loss. Pyotraumatic dermatitis, or hot spots, is a common skin problem in dogs that can also cause hair loss by excessive scratching and biting by the dog. The hot spots can often be on the dog’s trunk, so hair loss from hot spots may occur in the trunk area when the dog bites and scratches the inflamed spots.

• Ringworm
• Autoimmune and immune-mediated diseases, such as pemphigus foliaceus
• Demodectic mange (also called demodex mange)

Ringworm is a fungus that commonly appears on the face. Ringworm often causes hair loss around the eyes and muzzle due to the fungus weakening and breaking the hair shafts. Pemphigus foliaceus and other autoimmune or immune-mediated diseases are another cause of hair loss around the eyes and muzzle. Such immune system deficiencies can result in patches of red skin that forms pustules and turns crusty after hair loss around the eyes and muzzle occurs. The skin disease demodectic mange can also cause hair loss around the eyes and muzzle, especially in younger dogs with poor immune systems. A mite called demodex canis lives naturally in the hair follicles, but can create hair loss around the eyes and muzzle if the immune system can not keep the mites under control.

• Kidney problems
• Cancer
• Hormonal disorders such as diabetes and Cushing’s disease

Kidney problems may cause excessive thirst as the dog will usually try to replace the water that is being lost through the frequent urination that may occur. Cancerous tumors can be another cause of excessive thirst. Tumors may cause the blood to have abnormally high amounts of calcium which can cause a large loss of fluid that may trigger excessive thirst. Hormonal disorders such as diabetes and Cushing’s disease can also cause excessive thirst. Diabetes can cause excess urine production which the body may react to with excessive thirst in order to cause the animal to drink more to avoid dehydration. Cushing’s disease often produces too many hormones in the adrenal glands. As the adrenal cortex regulates the balance of fluids in the body, fluid imbalance and excessive thirst can result.

• Flea bite dermatitis
• Mange
• Allergies

Flea bite dermatitis often causes scratching and rubbing of the body when a dog is allergic to one or more of the many different allergens in flea saliva. A common spot for flea bite dermatitis is the base of the tail and the dog may begin chewing at the irritated spot as well as engage in scratching and rubbing of the body. Mange is a mite-related skin disease in dogs and it may cause scratching and rubbing of the body as the irritation of the skin by the mites usually causes extreme itchiness. Allergies of all types also cause extreme itchiness in dogs resulting in scratching and rubbing of the body. Biting the feet often accompanies scratching and rubbing of the body in dogs with allergies.

• Ear infections
• Demodectic mange (also called demodex mange)
• Allergies

Ear infections may cause scratching and rubbing of the face due to irritation caused by mites, bacteria or yeast. Demodectic mange is a skin disorder caused by the demodex canis mite and it may also cause scratching and rubbing of the face. Demodectic mange is often not that itchy, but can still be very irritating to dogs as the mites are often near the eyes and mouth and scratching and rubbing of the face may relieve some of the irritation. Allergies usually affect dogs by causing intense itchiness all over the body, so dogs irritated by allergens will often engage in scratching and rubbing of the face. Scratching and rubbing of the face on carpets or furniture is common behavior in dogs with allergies.

• Excess fluid in the lungs (edema) or chest (pleural effusion)
• Heart disease or heart failure
• Objects caught in the airway

Excess fluid in the lungs or chest as a result of a disease or an infection can cause labored breathing as well as coughing. A dog with labored breathing may be having trouble trying to get an adequate amount of oxygen into lungs that are blocked up with too much fluid. Heart disease or heart failure may also cause labored breathing and difficulty in obtaining oxygen as blood and fluid from a faulty heart may leak into the lungs. Labored breathing could also be a sign that something is caught in the dog’s airway. Foreign objects or tumors may cause labored breathing if they are putting pressure on the airway.

• Interdigital pyoderma (infection between the toes)
• Sprains
• Bone tumors

Interdigital pyoderma, or infection between the toes, can cause lameness or swelling as dogs often bite their feet when they are itchy from allergies which can create an infection. Dogs with lameness or swelling from an infection between the toes will usually avoid putting much pressure on the infected foot. Muscle, tendon, ligament and joint sprains can all cause lameness or swelling due to trauma or injury. Bone tumors may cause lameness or swelling and are usually located near the joints in leg bones. Bone tumors that cause extreme lameness or swelling can be very painful to the dog.

• Canine parvovirus
• Parasites
• Dental problems

Canine parvovirus is a potentially fatal viral disease that may cause lethargy. The parvovirus affects the gastrointestinal system very intensely as it usually causes bloody diarrhea and vomiting. Fever and dehydration may also accompany lethargy in dogs with canine parvovirus. Internal infections of parasitical worms are another cause of lethargy, as well as diarrhea, in dogs. Dental problems are a common cause of lethargy in older dogs. Dental problems can cause extreme mouth pain in dogs and weight loss and loss of appetite often accompany the lethargy.

• Dental problems
• Infection
• Disease

Dental problems can cause a loss of appetite due to mouth, gum or tooth pain or tenderness. Weight loss and lethargy often accompany a loss of appetite in dogs experiencing dental problems. Infections such as those caused by ticks or parasites can affect the gastrointestinal system and cause a loss of appetite. Diarrhea and lethargy often accompany infections and may make the dog feel very sick and experience a loss of appetite as a result. Many different diseases such as heart disease, distemper and cancer can also cause a loss of appetite.

• Intestinal parasites or bacteria
• Changes in diet
• Liver or kidney diseases

Intestinal parasites and bacteria may cause mild diarrhea, or even more severe cases of diarrhea, due to their affect on the gastrointestinal system. Mild diarrhea can also be attributed to changes in diet, such as the switch to a new dog food. A high fat diet may also cause mild diarrhea in dogs. Eating table scraps will also often cause a dog to have mild diarrhea. Liver and kidney diseases can also cause mild diarrhea or more severe diarrhea.

• Excessive scratching or rubbing of the body or face
• Cancer
• Pyoderma

Excessive scratching or rubbing of the body or face is often due either to allergies or to skin or ear infections and can cause open sores on the skin. Open sores on the skin are prone to bacterial and yeast infections. Open sores on the skin that do not heal could be a sign of cancer. Pyoderma, a bacterial skin infection, can also produce open sores on the skin because of deficiencies in the immune system. Loss of appetite, weight loss and pus-filled lumps often accompany open sores on the skin in pyoderma cases.

• Canine distemper
• Canine conjunctivitis (also called pink eye or red eye)
• Entropion

Canine distemper may cause pus-filled eyes. Loss of appetite, avoidance of water, fever, lethargy, vomiting, diarrhea and coughing may also accompany pus-filled eyes in canine distemper cases. Canine conjunctivitis, or pink eye or red eye, may cause pus-filled eyes due to inflammation. When the pus-filled eyes dry out they can be crusty and cause the eyes to stick together. Entropion is a genetic disorder in which the eyelids face inward rather than outward. Entropion may cause pus-filled eyes as the backwards eyelashes can irritate the eye’s surface.

• Canine conjunctivitis (also called pink eye or red eye)
• Uveitis
• Scleritis

Canine conjunctivitis, or pink eye or red eye, causes reddening of the eyes. The redness is created by inflammation, due to an injury or a bacterial or viral infection that results in increased blood flow to the eyes. Sensitivity to light and discharge from the eyes may accompany reddening of the eyes in conjunctivitis cases. Uveitis involves the inflammation of blood vessels in the eye which causes reddening of the eyes. Besides reddening of the eyes, sensitivity to light and/or spasms in the eyelids may occur in dogs with uveitis. Scleritis is an inflammatory disorder that may cause a sudden reddening of the eyes that may be firm and bumpy in appearance.

• Atopic dermatitis
• Mast Cell Tumor (MCT)
• Demodectic mange (also called demodex mange)

Atopic dermatitis is an allergic skin disorder that can cause redness of the skin. The redness of the skin may discolor to a black mottled look that is usually on the dog’s abdomen. A Mast Cell Tumor (MCT) often causes redness of the skin when the tumor is touched as histamines exit from the tumor. Demodectic mange is not usually itchy, but does often cause redness of the skin due to irritation to the skin near the eyes and mouth. The redness of the skin in demodectic mange may also have a crusty appearance.

• Back or neck pain
• Leptospirosis
• Lyme disease

Back or neck pain, often from muscle, nerve or vertebral problems, may cause a reluctance to move. Crying out when moving, loss of appetite and weakness may also accompany a reluctance to move when back or neck pain is present. The bacterial infection leptospirosis may also cause reluctance to move because of joint and muscle pain. Besides reluctance to move, dogs with leptospirosis may also experience vomiting, back pain and a loss of appetite. Lyme disease may also cause reluctance to move and/or stiffness when moving.

• Chocolate poisoning
• Gastric Dilatation Volvulus (GDV) (also called bloat)
• Canine epilepsy

The cocoa bean stimulant theobromine found in most chocolate products is extremely poisonous to dogs. Chocolate affects a dog’s heart and central nervous system and can first show up as restlessness and pacing. Vomiting, diarrhea, hyperactivity, muscle twitches and increased urination often accompany restlessness and pacing in cases of chocolate poisoning in dogs. Gastric Dilatation Volvulus (GDV), or bloat, can also cause restlessness and pacing in dogs as a result of the distress in having a twisted and bloated stomach. Restlessness may also be caused by canine epilepsy. The dog may either feel a seizure coming on or feel that something is not right within the body and react with restlessness and/or unusual behavior.

• Epilepsy
• Hypoglycemia (low blood sugar)
• Infection, disease or poisoning

Epilepsy causes seizures in dogs just as it does in humans, due to faulty nerve cells in the brain. Hypoglycemia, low blood sugar levels, may also cause seizures in dogs. Infections such as distemper can cause seizures as well as other behavioral changes such as walking in circles. Distemper as well as rabies often causes seizures due to encephalitis, or inflammation of the central nervous system. Poisoning such as from lead, antifreeze, chocolate or rat poison may also cause seizures as the dog’s body reacts to the toxins.

• Pain from muscular, skeletal or neurological disorder
• Salmonellosis
• Leptospirosis

Pain from a muscular, skeletal or neurological disorder such as a damaged disc can cause shaking and/or shivering in dogs. Faulty nervous system functioning can also cause shaking and/or shivering. Salmonellosis, a potentially fatal bacterial disease, is associated with younger dogs living in unclean conditions and is another cause of shaking and/or shivering. Diarrhea, fever and vomiting may also accompany shaking and /or shivering in salmonellosis cases. The bacterial infection leptospirosis affects the liver and kidneys and can cause shaking and/or shivering.

• Acral lick granuloma
• Bacterial infections
• Ectoparasites

Acral lick granuloma causes small skin lesions that dogs often lick, bite and irritate into raw, large skin lesions. Bacterial infections are another cause of skin lesions such as pustules that may turn crusty or scaly. Parasites of the skin, or ectoparasites, such as sarcoptes scabiel and cheyletiella cause itchy skin lesions. Scaling and reddening of the skin may occur on the surface of these types of mite-produced skin lesions.

• Normal discharge reflex
• Nasal infection or allergies
• Nasal, sinus or dental disease

Occasional sneezing is often normal as sneezing is a natural reflex for releasing irritants from the nose. Some discharge from the nose may occur with normal sneezing. More chronic sneezing and discharge may signal a viral or fungal nasal infection or allergies. Nasal, sinus or dental disease can also cause sneezing and discharge from the nose. Tumors in the nose may also cause irritation and sneezing.

• Brachycephalic Airway Obstruction Syndrome (BAOS)
• Paroxysmal respiration (also called reverse sneezing)
• Capillaria bohemi

Brachycephalic Airway Obstruction Syndrome (BAOS) often causes snuffling and snorting in breeds with shorter heads and muzzles such as bull dogs and Boston terriers. The snorting and snuffling sounds these breeds make are usually due to their soft palates and small nostril openings. Paroxysmal respiration, or reverse sneezing, is not really a reverse sneeze, but is frequently described that way to give an idea of what the snuffling and snorting often sounds like. It is a normal sound of many small dogs, especially brachycephalic, or shorter-muzzled breeds such as pugs. Snuffling and snorting may occur when the dog is an excited state and not as much air is reaching the small trachea, or windpipe. Capillaria bohemi, an intestinal worm, may also sometimes cause snuffling and snorting sounds and can be confused with whipworm. Capillaria bohemi is not as common as whipworm and often affects greyhounds.

• Sudden Acquired Retinal Degeneration (SARDS)
• Glaucoma
• Diabetes mellitus

Sudden Acquired Retinal Degeneration (SARDS) can cause sudden blindness. The dog may experience some vision trouble weeks or days before the sudden blindness occurs as well as excessive thirst and appetite. Glaucoma is another cause of sudden blindness due to pressure and/or fluid build up in the eye. Besides sudden blindness, glaucoma may also cause reddening of the eyes, enlarged and/or cloudy eyes, painful, closed eyes and a loss of appetite. Diabetes mellitus may cause sudden blindness due to the body’s faulty regulation of blood sugar to body tissues.

• Cardiomyopathy
• Aortic stenosis
• Heartworm infection

Cardiomyopathy, a heart muscle disease, may cause sudden death due to heart failure in some larger breeds that may be predisposed to the condition. Often, there are no other signs of cardiomyopathy besides sudden death. Aortic stenosis, an inherited disorder that affects the passageways to the aorta, may also cause sudden death in more severe cases without any other signs. Heartworm infection can also cause sudden death without other signs. The sudden death caused by heartworm may occur when the heartworms multiply in the heart chamber and severely limit blood flow.

• Neuromuscular disorders
• Plant or pesticide poisoning
• Neosporosis

Neuromuscular disorders can cause swallowing difficulties. Plant or pesticide poisoning can also cause swallowing difficulties. Many flowers are also toxic to dogs such as poinsettias and daffodils and can cause swallowing difficulties as well as breathing difficulties, vomiting and excessive salivation. The parasitic protozoan infection neosporosis can cause swallowing difficulties in puppies due to the paralysis caused by the disease. Neosporosis can lead to death or blindness. Muscle stiffness or atrophy and heart failure often accompany swallowing difficulties in cases of neosporosis.

• Dilated cardiomyopathy
• Spleen cancer
• Gastric Dilatation Volvulus (GDV) (also called bloat)

Dilated cardiomyopathy, a heart muscle disease, is common in larger dog breeds, particularly in younger males and may cause swelling of the abdomen as well as coughing, fainting, loss of appetite and exercise intolerance. The swelling of the abdomen can appear suddenly and dilated cardiomyopathy can go undetected for a long time. Spleen cancer may also cause swelling of the abdomen as well as weight loss. Gastric Dilatation Volvulus (GDV), or bloat, is a potentially deadly condition involving swelling of the abdomen. Bloat causes swelling of the abdomen as the stomach is twisted and air and fluid are caught in the abdomen.

• Ingestion of toxic plants
• Insect stings
• Dental infection

Ingestion of toxic plants such as the common houseplant philodendron can cause swelling of the mouth and throat in dogs. Many plants and flowers are potentially deadly to dogs and may cause kidney damage as well as swelling of the mouth and/or throat. Stings from bees or wasps are a common cause of swelling of the mouth in dogs due to the venom released by the stingers. A dental infection such as an abscessed tooth may cause swelling of the mouth and gums. Bad breath and swelling of the mouth that feels warm to the touch may indicate dental infection.

• Nasal disease
• Cuterebra
• Allergies

Nasal disease can cause swelling over the nose on the bridge. Discharge from the nose as well as sneezing may accompany swelling over the nose in nasal diseases. The larval skin infection cuterebra can also cause swelling over the nose on the bridge. Swelling of the throat and mouth, sneezing and labored breathing may accompany swelling over the nose in cases of cuterebra infection. Allergies such as grass pollen or other seasonal allergies are often another cause of swelling over the nose in dogs.

• Ingestion of toxic plants
• Juvenile cellulitis (also called juvenile pyoderma and puppy strangles)
• Reaction to allergies or throat trauma

Ingestion of toxic plants may cause swelling of the throat in dogs and many plants and flowers may cause death in some cases. Juvenile cellulitis, or juvenile pyoderma or puppy strangles, can cause swelling of the throat due to enlarged lymph nodes in the neck. Puppy strangles not only causes severe swelling of the throat, but of the puppy’s head as well. Reaction to allergies or throat trauma may cause an extreme swelling of the throat and can seriously limit the dog’s airway and cause choking. Gagging, breathing and swallowing problems and scratching or rubbing the face may occur in any condition that involves swelling of the throat.

• Canine laryngeal paralysis
• Nerve disorder related dysphagia (difficulty swallowing)
• Rabies

Canine laryngeal paralysis can cause throat and mouth paralysis due to the dysfunction of the larynx. Throat-clearing noises, panting and wheezing may accompany throat and mouth paralysis in canine laryngeal paralysis cases. Nerve disorder related dysphagia (difficulty swallowing) may also cause throat and mouth paralysis. The mouth’s muscles that chew and swallow food can be affected either with mild or severe throat and mouth paralysis. Rabies can also cause throat and mouth paralysis. A rabies infected dog at a certain stage of the disease can not swallow due to the paralysis, so excessive salivation occurs and this produces the mouth foaming that many people think of when they think of rabies. After the throat and mouth paralysis stage, rabies often affects the rest of the body and causes coma and death.

• Dietary changes
• Blocked passageways to the stomach
• Parasites

Changes in diet can cause vomiting in dogs. A high protein diet as well as table scraps or grass or garbage can cause vomiting. Swallowed foreign objects that block the passageways to the stomach are often a cause of vomiting as many dogs tend to swallow things they should not. Parasites are another cause of vomiting, especially in younger dogs with roundworm or hookworm infestation. Roundworms cause vomiting by creating intestinal blockage, while hookworms cause vomiting by creating inflammation in the intestinal lining.

• Neosporosis
• Distemper
• Systemic Lupus Erythematosus (SLE)

Neosporosis, a parasitic protozoan infection, can cause walking in circles due to the affects of the infection on the brain and muscles. Neosporosis may cause death or blindness in some cases. Distemper, a potentially deadly virus in dogs, is another cause of walking in circles. Seizures may accompany walking in circles in cases of distemper. Systemic Lupus Erythematosus (SLE) also causes walking in circles. SLE is unlike other forms of lupus in that it affects the whole body. Arthritis in several joints, kidney disease, weakness and fever may accompany walking in circles in cases of SLE.

• Degenerative myelopathy
• Diabetes mellitus
• Hemangiosarcoma

Degenerative myelopathy is a spinal cord disease that causes weakness in the hind legs of older dogs and may later affect the front legs. Dogs with degenerative myelopathy may drag their feet and walk in a wobbly gait due to the weakness in their legs caused by the disease. Diabetes mellitus may cause weakness due to abnormal blood sugar levels. Excessive thirst and urination as well as weight loss may accompany weakness in cases of diabetes mellitus. Hemangiosarcoma is a cancer involving blood vessel tumors that invade the organs such as the spleen, liver, heart and lungs. Weakness is common in cases of hemangiosarcoma.

• Anorexia (lack of appetite) and/or metabolic disorder
• Intestinal parasites
• Diabetes mellitus

Anorexia, or lack of appetite, may be a cause of weight loss in otherwise healthy dogs. A metabolic disorder can be another cause of weight loss. Intestinal parasites often cause chronic weight loss as most intestinal parasites have a strong affect on the body’s digestive system. Diarrhea and vomiting often accompany weight loss in most cases of intestinal parasites. Diabetes mellitus can cause weight loss despite the increased appetite and excessive thirst diabetic animals and people often experience.

• Alcohol poisoning
• Degenerative myelopathy
• Intervertebral Disc Disease (IVDD)

Alcohol is toxic to dogs. Vomiting and a wobbly gait are signs of alcohol poisoning in dogs and severe cases may lead to coma and death. Degenerative myelopathy is a spinal cord disease that often causes a wobbly gait in older dogs as it affects the hind legs. Weakness and dragging or crossing the feet often accompany a wobbly gait in dogs afflicted with degenerative myelopathy. Intervertebral Disc Disease (IVDD) is mostly found in small dogs and is another cause of a wobbly gait. IVDD causes the premature aging of the discs and leads to ruptures. A wobbly gait in dogs is often the predominant sign of Intervertebral Disc Disease due to damaged motor capacity.