Veterinary Internal Medicine
At Mount Carmel Animal Hospital in Northern Baltimore County, we offer more than a typical general practice. We have the expertise and advanced diagnostics to go beyond common illnesses and minor injuries. Our veterinarians are experienced in diagnosing and treating complex, chronic, and uncommon diseases. We can provide long-term disease management for conditions that don’t have a simple cure like diabetes, kidney failure, autoimmune disorders, and gastrointestinal diseases. We offer second opinions on cases that are unusual, severe, or difficult to diagnose. Just as with humans, an underlying issue can affect multiple body systems and can be challenging to diagnose and treat.
Internal medicine for pets is a veterinary specialty focused on diagnosing and treating diseases affecting internal body systems. Veterinarians specializing in internal medicine (often called veterinary internists) handle complex or chronic conditions related to the heart, lungs, liver, kidneys, gastrointestinal tract, immune system, endocrine system, and nervous system.
Common conditions treated in veterinary internal medicine include:
Endocrinology diseases
Endocrinology diseases in pets involve hormonal imbalances caused by issues with glands like the thyroid, adrenal glands, pancreas, and pituitary gland. Here are some common endocrine disorders in pets:
- Diabetes Mellitus (Dogs & Cats)
- Caused by insulin deficiency or resistance
- Symptoms: Increased thirst & urination, weight loss, increased appetite, lethargy
- Treatment: Insulin therapy, diet management, oral therapy (cats only)
- Hypothyroidism (Mostly in Dogs)
- Caused by an underactive thyroid gland
- Symptoms: Weight gain, lethargy, hair loss, cold intolerance, slow heart rate
- Treatment: Daily thyroid hormone replacement
- Hyperthyroidism (Mostly in Cats)
- Caused by an overactive thyroid gland (often due to a benign tumor)
- Symptoms: Weight loss despite increased appetite, hyperactivity, vomiting, diarrhea, increased heart rate
- Treatment: Medication, radioactive iodine therapy, or surgery. For cats: diet management
- Cushing’s Disease (Hyperadrenocorticism) (Dogs)
- Caused by excess cortisol production (often due to a tumor in the adrenal or pituitary gland)
- Symptoms: Increased thirst & urination, pot-bellied appearance, hair loss, panting, skin infections
- Treatment: Medications to reduce cortisol or surgery in some cases
- Addison’s Disease (Hypoadrenocorticism) (Dogs)
- Caused by insufficient cortisol production by the adrenal glands
- Symptoms: Lethargy, vomiting, diarrhea, weight loss, weakness, collapse (in severe cases)
- Treatment: Lifelong hormone replacement therapy
- Insulinoma (Dogs & Rarely Cats)
- Caused by a tumor in the pancreas that produces excess insulin
- Symptoms: Weakness, confusion, seizures, fainting due to low blood sugar
- Treatment: Surgery, medication, or dietary changes
- Acromegaly (Mostly in Cats)
- Caused by a tumor in the pituitary gland producing too much growth hormone
- Symptoms: Enlarged face/paws, weight gain despite diabetes, thickened skin
- Treatment: Radiation therapy, insulin therapy for diabetes management
- Diabetes Insipidus (Dogs & Cats)
- Caused by a lack of antidiuretic hormone (ADH), leading to excessive water loss
- Symptoms: Extreme thirst and urination, dehydration
- Treatment: Hormone replacement therapy
Gastroenterology diseases
Gastroenterology diseases in pets affect the digestive system, including the stomach, intestines, liver, pancreas, and esophagus. These conditions can cause vomiting, diarrhea, weight loss, or other gastrointestinal symptoms. Here are some of the most common gastroenterology diseases in pets:
- Inflammatory Bowel Disease (IBD) – Dogs & Cats
- Chronic inflammation of the stomach or intestines
- Symptoms: Chronic vomiting, diarrhea, weight loss, decreased appetite
- Cause: Unknown (possibly immune-related or dietary triggers)
- Treatment: Diet changes, medications (steroids, immunosuppressants, probiotics)
- Pancreatitis – Dogs & Cats
- Inflammation of the pancreas, leading to digestive enzyme overproduction
- Symptoms: Vomiting, diarrhea, abdominal pain, lethargy, decreased appetite
- Cause: High-fat diet, obesity, certain medications, or unknown triggers
- Treatment: Supportive care (fluids, pain meds, diet changes)
- Gastritis – Dogs & Cats
- Inflammation of the stomach lining
- Symptoms: Vomiting, decreased appetite, lethargy, abdominal discomfort
- Cause: Eating spoiled food, toxins, infections, allergies, foreign objects
- Treatment: Dietary changes, medications to reduce stomach acid & nausea
- Gastroesophageal Reflux Disease (GERD) – Dogs & Cats
- Acid reflux from the stomach into the esophagus
- Symptoms: Regurgitation, burping, lip licking, discomfort when eating
- Cause: Weak esophageal sphincter, hiatal hernia, anesthesia complications
- Treatment: Acid reducers, dietary changes, feeding adjustments
- Exocrine Pancreatic Insufficiency (EPI) – Mostly in Dogs
- Pancreas doesn’t produce enough digestive enzymes
- Symptoms: Chronic diarrhea, weight loss despite normal appetite, greasy stools
- Cause: Pancreatic atrophy or chronic pancreatitis
- Treatment: Lifelong enzyme supplementation, diet adjustments
- Liver Disease – Dogs & Cats
- Liver dysfunction due to infection, toxins, genetics, or aging
- Symptoms: Jaundice (yellow gums/skin), vomiting, diarrhea, lethargy, fluid buildup in abdomen
- Cause: Hepatitis, liver shunts, toxins, cancer
- Treatment: Depends on cause (medications, diet changes, surgery)
- Colitis – Mostly in Dogs
- Inflammation of the colon (large intestine)
- Symptoms: Frequent diarrhea, mucus or blood in stool, urgency to defecate
- Cause: Stress, infections, food intolerance, IBD
- Treatment: Diet modifications, probiotics, medications
- Megaesophagus – Dogs & Cats
- Esophagus loses its ability to move food to the stomach
- Symptoms: Regurgitation, weight loss, coughing, aspiration pneumonia risk
- Cause: Congenital defect or nerve/muscle disorders
- Treatment: Feeding in an upright position, special diet, medication
- Foreign Body Ingestion – Mostly in Dogs & Cats
- Pets swallow toys, bones, string, or other objects causing blockages
- Symptoms: Vomiting, lack of appetite, abdominal pain, lethargy
- Treatment: Surgery or endoscopy to remove object
- Parvovirus – Mostly in Puppies and unvaccinated dogs of all ages
- Highly contagious viral disease attacking the intestines.
- Symptoms: Severe vomiting, bloody diarrhea, dehydration, fever
- Treatment: Intensive care (fluids, antibiotics, hospitalization)
Pulmonology diseases
Pulmonology diseases in pets affect the respiratory system, including the lungs, trachea, bronchi, and nasal passages. These conditions can cause coughing, difficulty breathing, wheezing, and exercise intolerance. Here are some common pulmonology (respiratory) diseases in pets:
- Canine and Feline Asthma
- Chronic inflammation and narrowing of the airways
- Symptoms: Wheezing, coughing, labored breathing, open-mouth breathing (cats)
- Cause: Allergies, environmental irritants (dust, smoke, pollen)
- Treatment: Inhalers, steroids, bronchodilators, avoiding triggers
- Bronchitis (Chronic or Acute) – Dogs & Cats
- Inflammation of the bronchi (airways leading to the lungs)
- Symptoms: Persistent coughing (especially in dogs), wheezing, exercise intolerance
- Cause: Allergies, infections, irritants (smoke, dust), chronic airway disease
- Treatment: Anti-inflammatory medications, bronchodilators, lifestyle changes
- Pneumonia – Dogs & Cats
- Infection or inflammation of the lungs (bacterial, viral, fungal, or aspiration pneumonia)
- Symptoms: Coughing, fever, lethargy, nasal discharge, difficulty breathing
- Cause: Infections, inhaling food or foreign substances (aspiration), weakened immune system
- Treatment: Antibiotics (if bacterial), antifungals, oxygen therapy, supportive care
- Tracheal Collapse – Mostly in Small Breed Dogs
- Weakening of the tracheal cartilage, causing airway collapse
- Symptoms: Honking cough, wheezing, trouble breathing, worsens with excitement
- Cause: Genetic predisposition (common in Yorkies, Pomeranians, Chihuahuas)
- Treatment: Weight management, cough suppressants, bronchodilators, surgery in severe cases
- Brachycephalic Airway Syndrome – Flat-faced Breeds (Dogs & Cats)
- Restricted airflow due to short skull shape (brachycephalic breeds)
- Symptoms: Snorting, noisy breathing, snoring, overheating, exercise intolerance
- Common Breeds: Bulldogs, Pugs, Boxers, Persians
- Treatment: Weight management, surgery (to correct elongated soft palate or narrowed nostrils)
- Pulmonary Edema – Dogs & Cats
- Fluid buildup in the lungs, leading to difficulty breathing
- Symptoms: Labored breathing, coughing, restlessness, blue gums
- Cause: Heart disease, trauma, toxin exposure, electrocution
- Treatment: Oxygen therapy, diuretics, treating underlying cause
- Lung Tumors (Primary or Metastatic) – Dogs & Cats
- Cancer affecting the lungs (either originating in the lungs or spreading from another organ)
- Symptoms: Persistent cough, weight loss, lethargy, difficulty breathing
- Cause: Primary lung cancer or metastasis from another cancer
- Treatment: Surgery (if operable), chemotherapy, supportive care
- Infectious Respiratory Diseases (Kennel Cough & Feline Upper Respiratory Infections)
- Highly contagious infections affecting the airways
- Symptoms: Coughing, sneezing, nasal discharge, fever (in severe cases)
- Cause: Bacteria (Bordetella), viruses (Canine Influenza, Feline Herpesvirus, Calicivirus)
- Treatment: Antibiotics (if bacterial), antiviral meds, supportive care, vaccinations for prevention
- Pulmonary Hypertension – Dogs & Cats
- High blood pressure in the lungs
- Symptoms: Labored breathing, fainting, lethargy, coughing
- Cause: Heart disease, lung disease, chronic airway conditions
- Treatment: Medications to reduce blood pressure, managing underlying cause
- Diaphragmatic Hernia – Dogs & Cats
- Abnormal opening in the diaphragm allowing organs to move into the chest cavity
- Symptoms: Difficulty breathing, reduced lung capacity, weakness
- Cause: Birth defect or trauma (e.g., car accident)
- Treatment: Surgery to repair the hernia
Rheumatology diseases
Rheumatology diseases in pets affect the joints, muscles, and connective tissues, often leading to pain, inflammation, and mobility issues. These conditions are usually autoimmune, inflammatory, or degenerative in nature. Here are some common rheumatologic diseases in pets:
- Osteoarthritis (Degenerative Joint Disease) – Dogs & Cats
- Chronic joint inflammation due to cartilage deterioration
- Symptoms: Stiffness, limping, difficulty jumping or climbing, reluctance to exercise
- Cause: Aging, joint injuries, obesity, genetic predisposition (common in large breed dogs)
- Treatment: Pain management (NSAIDs, joint supplements, physical therapy)
- Immune-Mediated Polyarthritis (IMPA) – Dogs & Cats
- Autoimmune disease where the immune system attacks the joints
- Symptoms: Swollen, painful joints, stiffness, fever, lethargy
- Cause: Unknown (may be triggered by infections, vaccines, or other immune disorders)
- Treatment: Immunosuppressive drugs (steroids, cyclosporine)
- Rheumatoid Arthritis – Rare in Dogs & Cats
- Autoimmune arthritis that destroys joint cartilage
- Symptoms: Progressive joint pain, swelling, deformity, lameness
- Cause: Immune system attacking joint tissues
- Treatment: Immunosuppressants, pain management, physical therapy
- Systemic Lupus Erythematosus (SLE) – Dogs & Rare in Cats
- Autoimmune disease affecting joints, skin, kidneys, and blood cells
- Symptoms: Joint pain, skin lesions, fever, kidney issues, weakness
- Cause: Genetic predisposition, environmental triggers
- Treatment: Immunosuppressive therapy (steroids, other medications)
- Lyme Disease – Dogs & Rarely in Cats
- Tick-borne bacterial infection affecting joints and organs
- Symptoms: Joint pain, fever, lethargy, limping, swollen lymph nodes
- Cause: Borrelia burgdorferi bacteria transmitted by ticks
- Treatment: Antibiotics, pain management, tick prevention
- Hip Dysplasia – Mostly in Large Breed Dogs
- Malformation of the hip joint leading to arthritis
- Symptoms: Difficulty standing up, limping, stiffness, reluctance to run or jump
- Cause: Genetic (common in German Shepherds, Labradors, Golden Retrievers)
- Treatment: Weight management, joint supplements, pain medications, surgery in severe cases
- Elbow Dysplasia – Mostly in Large Breed Dogs
- Developmental disorder affecting the elbow joint
- Symptoms: Limping, front leg stiffness, reluctance to exercise
- Cause: Genetics, rapid growth, poor joint development
- Treatment: Pain management, surgery in severe cases
- Fibrotic Myopathy – Dogs (Especially German Shepherds)
- Muscle scarring and stiffness in the hind legs
- Symptoms: Shortened stride, stiff gait, muscle tightness
- Cause: Unknown (suspected trauma or chronic inflammation)
- Treatment: Physical therapy, pain management, surgery in severe cases
- Hypertrophic Osteodystrophy (HOD) – Large Breed Puppies
- Inflammation of growth plates in young, fast-growing dogs
- Symptoms: Lameness, swollen joints, pain, fever
- Cause: Rapid growth, genetics, immune system involvement
- Treatment: Pain relief, anti-inflammatory medications, supportive care
- Craniomandibular Osteopathy (CMO) – Terriers & Bulldogs
- Bone overgrowth in the skull and jaw
- Symptoms: Difficulty chewing, swollen jaw, drooling, pain
- Cause: Genetic (common in West Highland White Terriers, Scottish Terriers)
- Treatment: Pain management, anti-inflammatory medications
Cardiac diseases
Cardiac diseases in pets can affect their heart muscle, valves, electrical system, or blood vessels, leading to heart failure, abnormal rhythms, or circulation problems. Here are some common heart diseases in dogs and cats:
- Congestive Heart Failure (CHF) – Dogs & Cats
- Heart can’t pump blood efficiently, leading to fluid buildup in the lungs or abdomen
- Symptoms: Coughing, difficulty breathing, lethargy, swollen belly, fainting
- Cause: Underlying heart disease (valve disease, cardiomyopathy)
- Treatment: Medications (diuretics, ACE inhibitors, beta-blockers), low-sodium diet
- Mitral Valve Disease (MVD) – Mostly in Small Breed Dogs
- Degeneration of the mitral valve, causing blood to leak backward into the heart
- Symptoms: Coughing, heart murmur, exercise intolerance, fluid buildup
- Common Breeds: Cavalier King Charles Spaniel, Dachshunds, Chihuahuas
- Treatment: Medications to support heart function, lifestyle management
- Dilated Cardiomyopathy (DCM) – Mostly in Large Breed Dogs & Cats
- Heart muscle weakens and enlarges, reducing its ability to pump blood
- Symptoms: Lethargy, coughing, collapse, rapid breathing
- Common Breeds: Dobermans, Great Danes, Boxers
- Cause: Genetic, nutritional deficiencies (linked to grain-free diets in some cases)
- Treatment: Medications (pimobendan, ACE inhibitors, diuretics), taurine supplementation if deficient
- Hypertrophic Cardiomyopathy (HCM) – Mostly in Cats
- Thickening of the heart muscle, reducing heart function
- Symptoms: Open-mouth breathing, lethargy, fainting, sudden paralysis in hind legs (from blood clots)
- Common Breeds: Maine Coons, Ragdolls, Persians
- Treatment: Medications to relax the heart muscle and prevent clots (beta-blockers, blood thinners)
- Heartworm Disease – Dogs & Cats
- Parasites (heartworms) live in the heart and lungs, causing severe damage
- Symptoms: Coughing, exercise intolerance, difficulty breathing, collapse
- Cause: Mosquito-borne infection (Dirofilaria immitis)
- Treatment: Medications to kill worms (dogs); no approved treatment for cats, but symptoms can be managed
- Prevention: Monthly heartworm preventatives (oral or topical)
- Arrhythmias (Irregular Heartbeat) – Dogs & Cats
- Abnormal electrical activity in the heart, causing slow, fast, or erratic beats
- Symptoms: Weakness, fainting, lethargy, irregular pulse
- Cause: Genetic conditions, heart disease, electrolyte imbalances
- Treatment: Medications, pacemaker (in severe cases)
- Patent Ductus Arteriosus (PDA) – Puppies & Kittens
- Congenital defect where a fetal blood vessel fails to close after birth
- Symptoms: Heart murmur, difficulty breathing, stunted growth
- Cause: Birth defect (common in toy breeds)
- Treatment: Surgery to close the ductus
- Pericardial Effusion – Dogs & Cats
- Fluid buildup around the heart, restricting its ability to pump
- Symptoms: Weakness, collapse, difficulty breathing, swollen belly
- Cause: Cancer, infection, Heart failure, unknown (idiopathic)
- Treatment: Fluid drainage, surgery, treating underlying cause
- Aortic Stenosis – Large Breed Dogs
- Narrowing of the aortic valve, making it harder for blood to leave the heart
- Symptoms: Weakness, fainting, sudden death (in severe cases)
- Common Breeds: Boxers, Newfoundlands, Golden Retrievers
- Treatment: Beta-blockers, surgery in extreme cases
- Pulmonary Stenosis – Small & Brachycephalic Breeds
- Narrowing of the pulmonary valve, reducing blood flow to the lungs
- Symptoms: Exercise intolerance, fainting, rapid breathing
- Common Breeds: Bulldogs, Beagles, Chihuahuas
- Treatment: Balloon valvuloplasty (surgical procedure to widen the valve)
Renal diseases
Renal (kidney) diseases are relatively common in pets, especially as they age. Some of the most common kidney diseases in cats and dogs include:
- Chronic Kidney Disease (CKD)
- More common in: Cats (especially senior cats), but also seen in dogs.
- Causes: Aging, genetics, infections, toxins, high blood pressure, or underlying conditions.
- Symptoms: Increased thirst and urination, weight loss, vomiting, bad breath, lethargy, poor appetite.
- Treatment: Supportive care with special diets, fluids, medications, and blood pressure management.
- Acute Kidney Injury (AKI)
- More common in: Both dogs and cats.
- Causes: Toxins (e.g., antifreeze, lilies in cats, grapes/raisins in dogs), infections, dehydration, medications (e.g., NSAIDs), and shock.
- Symptoms: Sudden vomiting, loss of appetite, decreased urination or no urination, weakness.
- Treatment: Emergency veterinary care with IV fluids, toxin removal, and supportive treatment.
- Polycystic Kidney Disease (PKD)
- More common in: Persian and other long-haired cats, but can also occur in dogs.
- Causes: Genetic (inherited disorder).
- Symptoms: Enlarged kidneys, weight loss, increased thirst and urination, lethargy.
- Treatment: Supportive care, diet management, and monitoring.
- Kidney Stones (Nephrolithiasis)
- More common in: Dogs, but also seen in cats.
- Causes: High mineral levels in urine, urinary infections, diet, or genetic predisposition.
- Symptoms: Painful urination, blood in urine, frequent urination, lethargy.
- Treatment: Special diets, medications, surgical removal if necessary.
- Glomerulonephritis
- More common in: Dogs.
- Causes: Immune system disorders, infections, chronic inflammation, or cancer.
- Symptoms: Protein loss in urine, swelling (edema), increased thirst and urination, weight loss.
- Treatment: Managing the underlying cause, blood pressure medications, special diets.
- Kidney Infections (Pyelonephritis)
- More common in: Both dogs and cats.
- Causes: Bacterial infections traveling from the bladder or bloodstream.
- Symptoms: Fever, back pain, increased thirst and urination, lethargy.
- Treatment: Antibiotics, fluids, and treating any underlying urinary tract issues.
Early detection and treatment of kidney disease in pets can significantly improve their quality of life. Regular veterinary check-ups, blood tests, and urine tests are essential for catching kidney disease early.
Geriatric diseases
As pets age, they become more prone to geriatric diseases, affecting their joints, organs, metabolism, and cognitive function. Here are some common conditions in senior dogs and cats:
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- Chronic joint pain and stiffness due to cartilage breakdown
- Symptoms: Limping, difficulty standing up, reluctance to jump or climb
- Treatment: Joint supplements (glucosamine, chondroitin), NSAIDs, weight management, physical therapyOsteoarthritis (Degenerative Joint Disease) – Dogs & Cats
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- Brain aging, causing memory loss and behavioral changes
- Symptoms: Disorientation, confusion, disrupted sleep, increased anxiety, forgetting commands
- Treatment: Brain-supportive diets, supplements (SAM-e, omega-3s), medications (selegiline)Cognitive Dysfunction Syndrome (CDS) – “Pet Dementia”
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- Kidney function gradually declines, leading to toxin buildup
- Symptoms: Increased thirst/urination, weight loss, vomiting, bad breath
- Treatment: Special kidney diet, fluid therapy, medications to support kidney functionChronic Kidney Disease (CKD) – Dogs & Cats
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- Heart function declines, leading to congestive heart failure
- Symptoms: Coughing, labored breathing, lethargy, fainting
- Treatment: Medications (diuretics, ACE inhibitors), low-sodium diet, heart monitoringHeart Disease (Mitral Valve Disease, DCM, HCM) – Dogs & Cats
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- Body can’t regulate blood sugar properly
- Symptoms: Increased thirst/urination, weight loss despite eating, lethargy
- Treatment: Insulin injections (for both cats and dogs), special dietDiabetes Mellitus – Dogs & Cats
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- Tumors can develop in the skin, organs, or bones
- Symptoms: Lumps, weight loss, loss of appetite, lethargy
- Treatment: Surgery, chemotherapy, radiation, palliative careCancer (Various Types) – Dogs & Cats
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- Hypothyroidism (dogs): Underactive thyroid causes weight gain, sluggishness, hair loss
- Hyperthyroidism (cats): Overactive thyroid causes weight loss, hyperactivity, increased appetite
- Treatment: Medication, diet changes, surgery (hyperthyroidism), radioactive iodine therapy (cats)Hypothyroidism (Dogs) & Hyperthyroidism (Cats)
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- Liver function declines, leading to toxin buildup and digestion issues
- Symptoms: Jaundice (yellow gums/skin), vomiting, loss of appetite, lethargy
- Treatment: Special diet, medications to support liver functionLiver Disease – Dogs & Cats
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- Cataracts, retinal degeneration, and deafness are common in aging pets
- Symptoms: Bumping into objects, cloudy eyes, unresponsive to sounds
- Treatment: Managing environment, surgery (for cataracts), adjusting communication methodsVision & Hearing Loss – Dogs & Cats
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- Weakened bladder control leading to accidents
- Symptoms: Urine dribbling, frequent urination, wet bedding
- Treatment: Medications (proin, estrogen therapy), absorbent bedding, frequent bathroom breaksIncontinence – Dogs & Cats
- Dental Disease – Dogs & Cats
- Tooth decay, gum infections, and bad breath due to plaque buildup
- Symptoms: Bad breath, difficulty eating, drooling, swollen gums
- Treatment: Professional dental cleanings, tooth extractions, daily brushing
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- Progressive spinal cord disease causing hind leg weakness and paralysis
- Symptoms: Dragging back legs, wobbliness, difficulty standing
- Treatment: Physical therapy, mobility aids (wheelchairs), supportive careDegenerative Myelopathy – Mostly in Large Breed Dogs
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- Overproduction of cortisol from adrenal glands
- Symptoms: Increased thirst/urination, pot-bellied appearance, hair loss
- Treatment: Medications (trilostane, mitotane), monitoring hormone levelsHyperadrenocorticism (Cushing’s Disease) – Dogs
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- Low red blood cell count leading to weakness and fatigue
- Symptoms: Pale gums, lethargy, rapid breathing
- Cause: Kidney disease, chronic illness, bone marrow disease
- Treatment: Treating underlying cause, supplements, blood transfusions (severe cases)Anemia – Dogs & Cats
- Geriatric Anxiety – Dogs & Cats
- Increased anxiety due to sensory decline, confusion, or loss of routine
- Symptoms: Restlessness, excessive vocalization, pacing, separation anxiety
- Treatment: Calming supplements, pheromones, anxiety medications, routine consistency
With our highly skilled team of veterinarians paired with in-house advanced diagnostics, we can diagnose, treat, and prevent diseases of your pet’s internal organs: heart, lungs, nervous system, intestinal tract, liver and pancreas, kidney and urinary tract.