The Importance of Regular Blood Work for Pets Over 7

Your pet may seem perfectly healthy—eating well, playing normally, showing no signs of illness. Yet underneath this apparent wellness, serious diseases can be quietly developing. This is the challenge of senior pet care: many conditions progress silently until they reach advanced stages where treatment becomes difficult or impossible.

Regular blood work is your window into your pet's internal health, revealing problems before they become visible. For pets over seven years old—considered senior for most dogs and cats—routine blood screening becomes one of the most valuable preventive care tools available.

📈 Why Age 7 Marks a Turning Point

While a 7-year-old pet may still act youthful, physiologically they're entering their senior years. Dogs and cats age approximately 4-7 years for every human year (depending on size and species), meaning a 7-year-old pet is roughly equivalent to a 44-60 year old human.

This is when age-related diseases begin emerging:

• Kidney disease becomes increasingly common, affecting 1 in 3 cats and many dogs
• Liver disease, thyroid disorders, and diabetes increase in frequency
• Cancer risk rises significantly with age
• Organ function gradually declines even in healthy pets

Regular blood work creates a baseline of your pet's normal values, making it easier to detect subtle changes that indicate emerging disease.

💉 What Blood Tests Reveal

Complete Blood Count (CBC)

A CBC examines the cellular components of blood, providing crucial information about overall health and immune function.

Red blood cells: Low counts indicate anemia, which can result from bleeding, chronic disease, bone marrow problems, or parasites. High counts may suggest dehydration or rare blood disorders.

White blood cells: Elevated counts point to infection, inflammation, or stress. Low counts indicate immune suppression or bone marrow disease. Different types of white blood cells provide specific clues about disease processes.

Platelets: These cells enable blood clotting. Low platelet counts increase bleeding risk and may indicate immune disease, bone marrow problems, or certain medications' side effects.

Chemistry Panel (Blood Chemistry)

This panel evaluates organ function and metabolic health by measuring various substances in blood.

Kidney function (BUN and Creatinine): These waste products normally filtered by kidneys accumulate when kidney function declines. Early detection allows dietary changes and medications that slow disease progression. However, by the time these values become abnormal, approximately 75% of kidney function is already lost—emphasizing why baseline testing matters.

Liver enzymes (ALT, AST, ALP, GGT): Elevated enzymes indicate liver cell damage or cholestasis (blocked bile flow). Different patterns help diagnose specific liver conditions, from hepatitis to cancer. Some medications also affect liver values, making monitoring essential.

Total protein and albumin: Low protein levels can indicate liver disease, kidney disease, intestinal problems, or protein loss through inflammation. High levels may suggest dehydration or certain cancers.

Glucose: Elevated glucose indicates diabetes, while low glucose suggests insulin-producing tumors, severe liver disease, or sepsis.

Electrolytes (sodium, potassium, chloride): Imbalances can be life-threatening and indicate kidney disease, Addison's disease, or other hormonal disorders.

Calcium and phosphorus: Abnormalities may indicate kidney disease, parathyroid problems, or certain cancers.

Additional Tests for Senior Pets

Thyroid hormone (T4): Hyperthyroidism is extremely common in senior cats, causing weight loss despite increased appetite, hyperactivity, and heart problems. Early detection allows simple medication to manage the condition.

For dogs, hypothyroidism (low thyroid) is more common, causing weight gain, lethargy, and skin problems.

Urinalysis: While not blood work, urinalysis complements blood tests by detecting kidney disease, diabetes, urinary tract infections, and bladder stones before symptoms develop.

🔍 The Power of Early Detection

Chronic Kidney Disease: A Prime Example

Kidney disease is progressive and irreversible, but early detection dramatically improves outcomes. When caught in early stages through blood work changes, kidney disease can be managed with:

• Prescription kidney diets that reduce protein waste
• Medications to control blood pressure and reduce protein loss
• Subcutaneous fluid therapy to support kidney function
• Treatment of underlying causes when identified

Pets diagnosed and managed early can live years with good quality of life. Those diagnosed in kidney failure have limited treatment options and much shorter survival times.

Diabetes Mellitus

Catching diabetes early, before pets develop diabetic ketoacidosis (a life-threatening emergency), allows for smoother regulation with insulin. Early intervention also reduces the risk of complications like cataracts and recurrent infections.

Liver Disease

The liver has remarkable regenerative capacity if disease is caught early. Identifying liver problems through blood work allows treatment of underlying causes, dietary management, and medications to support liver function before irreversible damage occurs.

Hyperthyroidism in Cats

This condition is extremely treatable with medication, radioactive iodine therapy, or surgery when detected. However, untreated hyperthyroidism causes heart disease, high blood pressure, and progressive weight loss that can become irreversible.

📅 Recommended Frequency for Senior Pet Blood Work

For Healthy Senior Pets (7-10 years)

Annually: Comprehensive blood work including CBC, chemistry panel, and thyroid testing (T4 for cats, consider for dogs if symptoms present).

This yearly screening catches most diseases in early stages while allowing you to track trends over time.

For Geriatric Pets (10+ years)

Every 6 months: Many veterinarians recommend twice-yearly blood work for geriatric pets because disease can progress rapidly at advanced ages.

Six-month intervals provide better monitoring and earlier intervention opportunities.

For Pets on Long-Term Medications

As directed by your veterinarian: Many medications require monitoring for side effects or dose adjustments:

• Arthritis medications (NSAIDs): Monitor kidney and liver function every 3-6 months
• Seizure medications: Check liver enzymes and drug levels regularly
• Thyroid medications: Monitor thyroid hormone levels to ensure proper dosing
• Chemotherapy: Frequent monitoring of blood cell counts

Before Anesthesia

Pre-anesthetic blood work is crucial for senior pets. Even if recent blood work was normal, checking values before procedures requiring anesthesia ensures your pet can safely metabolize anesthetic drugs and identifies any changes that affect anesthetic protocols.

💰 Understanding the Investment

Senior blood work panels typically cost $150-$300 depending on location and which tests are included. While this represents an expense, consider the value:

• Early detection saves money: Managing early-stage kidney disease with prescription diet and medication costs far less than treating kidney failure with hospitalization and intensive care
• Peace of mind: Normal blood work provides reassurance your pet's internal health matches their outward appearance
• Treatment effectiveness: Early intervention is more successful, less invasive, and less expensive than treating advanced disease
• Quality of life: Catching diseases early prevents suffering and maintains your pet's quality of life longer

Many pet insurance policies cover routine wellness blood work for senior pets. Check your policy or consider wellness plans offered by veterinary practices.

💬 Questions to Ask Your Veterinarian

Make the most of blood work by asking:

• "Which specific tests are included in the senior panel?"
• "What are my pet's results, and how do they compare to their baseline?"
• "Are any values trending in a concerning direction, even if still normal?"
• "Based on these results, should we change anything about diet, supplements, or monitoring frequency?"
• "Can I get a copy of results for my records?"

Taking Action for Your Senior Pet

If your pet is over 7 and hasn't had blood work in the past year, schedule a senior wellness exam. Even if your pet seems perfectly healthy, establishing baseline values now makes future monitoring more effective.

For pets already receiving regular blood work, ensure you understand the results and maintain copies in your pet health records. Ask your veterinarian to explain any trends they're watching, even if current values appear normal.

As our pets age, they rely on us to be their advocates. They can't tell us when they feel "off" or when something hurts. Regular blood work gives voice to their internal health, allowing us to provide the proactive care that can add years to their lives and life to their years.

Your senior pet has given you years of unconditional love. Investing in routine blood work is one of the most meaningful ways to return that devotion and ensure they enjoy their golden years to the fullest.