The word 'sick dog' does not tell you anything about the medical condition of the dog. Dog may become sick due to several reasons. Sickness in dogs may not be as evident as sickness in humans. The fact that a dog cannot communicate his discomfort makes diagnosis and detection of dog's sickness even more difficult. However, if you have experience with dogs or pets in general, you must have seen that they have their own way of conveying their illness. Vigilant dog owners can detect even smallest changes in dog behavior. A sick dog will behave as differently as possible from a healthy dog. The nature of behavior is mostly dependent upon the underlying health problem.

Sick Dog Diagnosis Chart

Diagnosis of a dog's illness can be done based on the symptoms exhibited by the dog. Given below is a detailed chart for dog illness symptoms and corresponding sickness.

Symptoms Causes
Abdominal Pain Canine Hepatitis, Dog Constipation, Canine Enteritis
Abdominal Swelling Canine Bloating, Roundworms (puppies)
Aggression Rabies
Anemia Roundworms, Tapeworms, Whipworms
Bad Breath Canine Bad Breath
Behavior Changes Hookworms, Canine Arthritis, Canine Heart Disease, Rabies, Red Mange - Demodectic, Canine Parvovirus, Tapeworms, Whipworms
Bloating Canine Bloating
Blood in Urine Canine Kidney Disease
Blood in Feces Dog Constipation
Bloodshot Eyes Canine Eye Infections, Entropion
Breathing difficulties Canine Heart Disease, Heartworms, Rabies, Canine Parvovirus, Dog Allergies, Ruptured Diaphragm, obstructed Airway, Lungworm, Bronchitis, Pneumonia, Heatstroke, Poisoning
Change in body weight Canine Heart Disease, Heartworms, Hookworms, Roundworms, Whipworms
Coma Rabies
Constipation Dog Constipation, Intestinal Obstruction, Hernia
Convulsions Canine Epilepsy
Coughing Canine Distemper, Canine Heart Disease, Heartworms, Canine Hepatitis, Kennel Cough, Roundworms, Canine Parvovirus, Dog Allergies, Lungworm, TB, Pneumonia
Deafness Canine Deafness
Dehydration Canine Parvovirus
Depression Canine Parvovirus
Diarrhea Canine Diarrhea, Distemper, Canine Enteritis, Canine Hepatitis, Hookworms, Canine Kidney Disease, Canine Parvovirus, Roundworms (puppies), Whipworms, Dog Allergies, Food Poisoning, IBS, Addison's Disease, Pancreatic Disorder
Drinking excessively Canine Kidney Disease
Ear Scratching Dog Ear Infections (Otitis Externa), Fleas, Dog Allergies
Eye Problems Distemper, Canine Eye Infections, Conjunctivitis, Entropion, Kennel Cough, Dog Allergies
Fainting Canine Heart Disease, Heartworms
Falling Canine Epilepsy, Wobbler Syndrome
Fever Kennel Cough, Rabies, Red Mange- Demodectic, Canine Parvovirus, Distemper, Canine Hepatitis, Lyme Disease, Canine Kidney Disease, Heatstroke, Food Poisoning / Toxic Poisoning, Canine Diabetes, Heart Disease
Fits Canine Epilepsy
Hair loss Mange, Red Mange - Demodectic, Scabies - Sarcoptic Mange, Dandruff - Cheyletiella Mange, Dog Allergies, Cushings Syndrome, Over-Active Thyroid, Fleas, Ringworm, Dog Allergy
Head Shaking Dog Ear Infections (Otitis Externa), Fleas
Inflammation Canine Arthritis, Mange, Inflamed Joints, Canine Arthritis, Lyme Disease
Itching Fleas, Dog Mange, Scabies - Sarcoptic Mange, Tapeworms, Ticks, Dandruff - Cheyletiella, Mange, Dog Allergies
Loss of appetite Canine Heart Disease, Heartworms, Kennel Cough, Lyme Disease, Rabies, Red Mange - Demodectic
Lack of coordination Wobbler Syndrome
Lack of response to sound Canine Deafness
Lameness Canine Arthritis, Hip Dysplasia, Lyme Disease, Patellar Luxation, Rabies, Wobbler Syndrome, Interdigital Cysts, Poisoning (Warfarin), Aortic Thrombosis
Lethargy Canine Arthritis, Canine Heart Disease, Hookworms, Kennel Cough, Canine Kidney Disease, Lyme Disease, Canine Parvovirus, Roundworms, Scabies - Sarcoptic Mange, Tapeworms, Whipworms
Nasal Discharge Distemper, Kennel Cough, Dog Allergies
Pain on movement Canine Arthritis, Hip Dysplasia
Panting Canine Heart Disease (refer breathing difficulty for additional causes)
Paralysis Rabies
Rectal bleeding Dog Constipation
Retching Canine Bloating, Kennel Cough
Salivation Canine Bloating, Rabies, Heatstroke, Poisoning, Epilepsy, Scabies - Sarcoptic Mange, Dandruff - Cheyletiella Mange, Dog Allergies, Scaly Skin, Red Mange - Demodectic, Scabies - Sarcoptic Mange
Scratching Fleas, Mange, Red Mange - Demodectic, Scabies - Sarcoptic Mange, Tapeworms, Ticks, Dandruff - Cheyletiella Mange, Dog Allergies, Seizure, Distemper, Canine Epilepsy, Canine Hepatitis, Canine Kidney Disease, Rabies
Twitching Distemper
Urinating problems Canine Kidney Disease
Vomiting Canine Bloating, Distemper, Canine Enteritis, Canine Hepatitis, Canine Kidney Disease, Canine Parvovirus, Tapeworms, Roundworms, Dog Allergies, Food/Toxic Poisoning, Diabetes, Addison's Disease, IBS, Over-eating, Food Allergy
Weight Loss Canine Heart Disease, Heartworms, Hookworms, Roundworms, Whipworms
Wheezing Kennel Cough

The above sick dog symptom checker is provided only for information. Do not refer to it for diagnosis or treatment of your own. Every dog is different and may have unique symptoms for a particular illness. Hence, it is best to take him to a vet if he exhibits any of the above symptoms.