Understanding Your Cat's Blood Work During FIP Treatment: A Complete Guide for Cat Owners

Blood tests are one of the most essential diagnostic tools used by veterinarians to evaluate your cat's health — especially in Feline Infectious Peritonitis (FIP) cases. Understanding the key components helps you follow your cat's progress during the 84-day GS-441524 protocol and have more informed conversations with your vet.

Not yet at the treatment stage? Start with our complete FIP action guide to understand the diagnosis process first.

Complete Blood Count (CBC)

The CBC measures the different components of your cat's blood and is usually the first test performed. Here is what each result means in the context of FIP:

Red Blood Cell Count (RBC)

  • Low RBC can indicate anaemia, commonly seen in FIP and chronic illness. Improvement during GS-441524 treatment is a positive sign.
  • High RBC may suggest dehydration.

White Blood Cell Count (WBC)

  • Elevated WBC may indicate infection, inflammation, or stress — common in active FIP.
  • Low WBC (particularly low lymphocytes) is a classic FIP pattern and should be monitored closely during treatment.

Platelet Count

  • Low platelets can lead to poor clotting and may signal bone marrow involvement or severe infection. Platelet recovery during GS-441524 treatment is a positive indicator.

Biochemistry Profile

This panel evaluates organ function and metabolic health. Key markers to review during FIP treatment:

  • ALT (Alanine Aminotransferase): High levels suggest liver damage or inflammation. Elevated ALT is common in FIP and should normalise as treatment progresses.
  • BUN (Blood Urea Nitrogen) & Creatinine: Elevated levels may indicate kidney disease or dehydration. Monitor throughout the 84-day protocol.
  • Glucose: High glucose can point to stress; low glucose may suggest poor nutrition. Supporting your cat's diet during treatment matters — see our FIP diet guide.
  • Total Protein (TP): High TP can indicate dehydration or inflammation. Low TP may reflect protein loss due to liver or kidney involvement.

The Most Important FIP-Specific Markers

When FIP is suspected or confirmed, these markers are evaluated most closely — and tracked throughout GS-441524 treatment to confirm the protocol is working.

Albumin-to-Globulin (A:G) Ratio

This is the single most important blood marker in FIP diagnosis and monitoring.

  • An A:G ratio below 0.6 is highly suggestive of FIP.
  • An A:G ratio below 0.4 is strongly indicative of FIP.
  • As GS-441524 treatment takes effect, the A:G ratio typically improves — rising back toward normal range is one of the clearest signs the protocol is working.

This is why your vet should run blood work every 30 days throughout the 84-day GS-441524 protocol. Tracking the A:G ratio over time is more informative than any single result.

Globulin Levels

Elevated globulins indicate chronic inflammation or an active immune response — both hallmarks of FIP. Falling globulin levels during treatment are a positive sign.

Albumin Levels

Low albumin is common in FIP, particularly wet FIP where protein leaks into fluid. Rising albumin during GS-441524 treatment indicates the body is recovering.

Bilirubin

High bilirubin levels indicate liver dysfunction, often associated with FIP. Yellowing of the gums or eyes (jaundice) is the visible sign of elevated bilirubin. Improvement here during treatment confirms the liver is recovering.

Electrolytes

Electrolytes are essential for cellular function and reflect hydration status:

  • Sodium (Na) & Potassium (K): Imbalances may signal dehydration, kidney disease, or metabolic issues.
  • Chloride (Cl): Low chloride is often linked to vomiting or kidney problems.

Keeping your cat well-nourished and hydrated throughout the 84-day protocol supports electrolyte balance. Our FIP diet guide covers practical feeding strategies during treatment.

What Improving Blood Work Looks Like During GS-441524 Treatment

Most cats on the correct GS-441524 dose show measurable blood work improvement within the first 30 days. Here is what to look for:

  • A:G ratio rising toward 0.6 or above
  • Globulin levels falling
  • Albumin levels rising
  • RBC and platelet counts recovering
  • ALT and bilirubin normalising
  • Lymphocyte count improving

If blood work is not improving after 30 days, discuss with your vet whether the dose needs to be adjusted. Under-dosing is the most common reason GS-441524 treatment stalls. See our FIP relapse guide for more on what happens when the protocol is not completed correctly.

How to Read Results in Context

Two principles every FIP cat owner should keep in mind:

  • Context matters. Blood test results must always be interpreted alongside your cat's clinical symptoms, history, and other diagnostic findings. A single abnormal value is rarely the full picture.
  • Trends are key. A single result tells you where your cat is today. A series of results taken every 30 days tells you whether the treatment is working. Always keep copies of every blood panel from day 1 through to the end of the observation period.

The Recommended Blood Test Schedule During GS-441524 Treatment

  • Day 0 (before starting): Full baseline panel including CBC, biochemistry, A:G ratio, and bilirubin
  • Day 30: Full repeat panel to confirm treatment response
  • Day 60: Full repeat panel to assess continued progress
  • Day 84 (end of treatment): Full panel before entering the 12-week observation period
  • Week 12 post-treatment: Final panel to confirm sustained remission

Your veterinarian may recommend additional tests depending on your cat's form of FIP and clinical response. For a full overview of what to expect at each stage, read our guide on FIP treatment outlook and recovery.

FIP CURE Plus GS-441524 Injectables

FIP CURE Plus supplies GS-441524 in two concentrations to match your cat's form of FIP and weight-based dose:

All pricing is listed openly in AED. View the full FIP CURE Plus product range.

Frequently Asked Questions

What is the most important blood test for FIP?
The albumin-to-globulin (A:G) ratio. A ratio below 0.6 is highly suggestive of FIP; below 0.4 is strongly indicative. Tracking this ratio every 30 days during GS-441524 treatment is the clearest way to confirm the protocol is working.

How often should blood work be done during FIP treatment?
Every 30 days throughout the 84-day GS-441524 protocol, plus a baseline before starting and a final panel at the end of the 12-week observation period.

What blood markers improve first during GS-441524 treatment?
Most cats show improvement in the A:G ratio, globulin levels, and general inflammation markers within the first 30 days. RBC and platelet recovery typically follows.

What if blood work is not improving after 30 days?
Discuss with your vet whether the dose needs adjustment. Under-dosing is the most common reason treatment stalls. Read our FIP relapse guide for more detail.

Can I monitor my cat's FIP treatment at home?
You can track weight, temperature, appetite, and energy daily. Blood work must be done by your veterinarian. Both are essential — clinical signs and lab results together give the full picture.

Conclusion

Blood tests are not just a diagnostic tool — they are your window into whether GS-441524 is working. Understanding the A:G ratio, globulin trends, and organ function markers puts you in a position to have informed conversations with your vet and catch any issues early.

If your cat has been diagnosed with FIP and you have questions about starting the GS-441524 protocol or interpreting blood results, the FIP CURE Plus team is available in English and Arabic at info@fipcureplus.com.

View the FIP CURE Plus GS-441524 injectable range →

FIP CURE Plus — transparent, evidence-based GS-441524 treatment for cats across the Gulf.

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