How Much Does FIP Treatment Cost for a Cat in the US?

Key takeaway: In the US, the cost of treating Feline Infectious Peritonitis (FIP) with GS-441524 depends on three things: your cat's weight, the FIP type (which sets the dose in mg/kg), and the product and strength you and your veterinarian choose. At CureFIP, GS-441524 Antiviral Injectables start at $49.00 for the 15 mg/ml, 8ml presentation and run up to $119.00 for the 40 mg/ml presentation, and the standard course runs 84 days under veterinary supervision. Below we break down exactly what drives the total so you can plan with confidence.

GS-441524 is the antiviral at the core of modern FIP treatment, with a 92% success rate reported by UC Davis (Pedersen, 2019) for monotherapy injectables. More than 100,000 cats have been treated across our network since 2019. We are clear about what the data shows and what it does not, and we are upfront about protocol, dosing structure, and cost.

How Much Does FIP Treatment Cost for a Cat in the US?

What determines the cost of FIP treatment?

The cost of FIP treatment is set by four factors: your cat's body weight, the FIP type (wet, dry, ocular, or neurological), the GS-441524 product and strength you select, and the length of the protocol, which is 84 days. Heavier cats and higher-dose FIP types use more medication, so they cost more across the full course.

Here is how each factor works:

• Body weight. GS-441524 is dosed per kilogram, so a larger cat needs more milligrams each day.

• FIP type. The daily dose in mg/kg rises from wet to dry to ocular and neurological FIP. Higher mg/kg means more product used per day.

• Product and strength. A higher concentration delivers more milligrams per milliliter, which can change how many vials a full course needs.

• Protocol length. A standard course runs 84 days (12 weeks) of daily treatment, so the daily amount is multiplied across the full schedule.

Because every cat's weight and FIP type are different, your veterinarian calculates the exact daily dose. We provide the per-product prices and the official dosing figures so you can plan the total with your vet.

What are the four types of FIP and how do they affect dosing?

FIP takes four forms, wet, dry, ocular, and neurological, and each one sets a different daily dose in mg/kg. The dose rises as the disease moves from the effusive form to the forms that involve the eyes and central nervous system, which is why FIP type is a major cost driver.

Wet (effusive) FIP

Wet FIP is the effusive form, marked by fluid buildup in the abdomen or chest. The GS-441524 Antiviral Injectables dose for wet FIP is 6 mg/kg, given as 1 subcutaneous injection per day, 7 days a week, for 84 days (reference: Pedersen et al., UC Davis, PMC6435921).

Dry (non-effusive) FIP

Dry FIP is the non-effusive form, where inflammatory lesions form in organs without significant fluid. The GS-441524 Antiviral Injectables dose for dry FIP is 8 mg/kg, given as 1 subcutaneous injection per day, 7 days a week, for 84 days.

Ocular FIP

Ocular FIP involves the eyes, with signs such as color change, cloudiness, or inflammation. The GS-441524 Antiviral Injectables dose for ocular FIP is 10 mg/kg, given as 1 subcutaneous injection per day, 7 days a week, for 84 days.

Neurological FIP

Neurological FIP involves the central nervous system, with signs such as wobbliness, seizures, or behavior changes. The GS-441524 Antiviral Injectables dose for neurological FIP is 10 mg/kg, given as 1 subcutaneous injection per day, 7 days a week, for 84 days.

Because ocular and neurological FIP use the highest mg/kg dose, they typically require more medication per day than wet or dry FIP for a cat of the same weight.

How much do GS-441524 injectables cost in the US?

GS-441524 Antiviral Injectables at CureFIP are priced by concentration, starting at $49.00 for the 15 mg/ml, 8ml presentation and rising to $119.00 for the 40 mg/ml presentation. Each product follows the same dosing schedule: 1 subcutaneous injection per day, 7 days a week, for 84 days.

Product

Strength

Volume

Price

GS-441524 Antiviral Injectables

15 mg/ml

8ml

$49.00

GS-441524 Antiviral Injectables

20 mg/ml

8ml, 10ml

$69.00

GS-441524 Antiviral Injectables

30 mg/ml

8ml, 10ml

$89.00

GS-441524 Antiviral Injectables

40 mg/ml

8ml, 10ml

$119.00

The higher concentrations deliver more milligrams per milliliter, which can suit larger cats or higher-dose FIP types. Your veterinarian will match the strength to your cat's weight and FIP type so each injection volume stays practical.

Are there GS-441524 injectables with added B12?

Yes. CureFIP offers GS-441524 Antiviral with Vitamin B12 in two strengths for cats who may benefit from added B12 support during treatment. The 20 mg/ml + B12 50 mcg/ml presentation is $75.00, and the 30 mg/ml + B12 50 mcg/ml presentation is $95.00.

Product

Strength

Volume

Price

GS-441524 Antiviral with Vitamin B12

20 mg/ml + B12 50mcg/ml

8ml, 10ml

$75.00

GS-441524 Antiviral with Vitamin B12

30 mg/ml + B12 50mcg/ml

8ml, 10ml

$95.00

These products follow the same dosing schedule as the standard injectables: dose by FIP type (wet 6 mg/kg, dry 8 mg/kg, ocular 10 mg/kg, neurological 10 mg/kg), 1 subcutaneous injection per day, for 84 days. Whether your cat needs added B12 is a decision for your veterinarian.

How much do oral FIP capsules cost?

Cure FIP™ Oral Capsules are priced at $129.00 and are dosed by weight band, with 1 capsule per day for a recommended 12 weeks. They combine GS-441524 with EIDD-1931 in a dual oral route positioned for wet and dry FIP.

Weight band

GS-441524

EIDD-1931

Under 5.5 lb

25 mg

5 mg

5.5 to 11 lb

35 mg

8 mg

Over 11 lb

50 mg

12 mg

For the dual antiviral route, evidence shows 78.3% remission (Li and Cheah, 2025). Note that some regions advise the oral dual route is not recommended once ocular or neurological signs are present, or if the cat cannot eat or defecate. Your veterinarian will confirm whether the oral route fits your cat.

CureFIP also lists EIDD-1931 Oral Capsules at $39.00, dosed at 1 capsule (15 mg) per 2.5 kg body weight every 12 hours, with 60 capsules per bottle and a standard 60-day course. EIDD-1931 is not for ocular or neurological cases, or for cats that are not eating or defecating, and it is teratogenic, so it should not be used in pregnant or lactating queens.

Injectable vs oral: which route fits which cat?

The injectable route uses GS-441524 monotherapy and is suited to all four FIP types, while the oral dual route is positioned for wet and dry FIP. The two routes are matched to different evidence, so they should be compared on suitability, not just price.

Route

Product

Best for

Matched evidence

Injectable (monotherapy)

GS-441524 Antiviral Injectables

Wet, dry, ocular, and neurological FIP

92% success rate (UC Davis, Pedersen 2019)

Oral (dual antiviral)

Cure FIP™ Oral Capsules

Wet and dry FIP

78.3% remission (Li and Cheah, 2025)

These two figures apply to different protocols and must not be combined or averaged. Your veterinarian will help you choose the route based on your cat's FIP type, weight, and ability to take medication.

How do you estimate the total cost for your cat?

To estimate the total cost of an 84-day GS-441524 course, you combine your cat's daily dose with the product price and the number of vials or capsules the full protocol requires. Because the daily dose depends on your cat's exact weight and FIP type, this calculation should be done with your veterinarian.

A practical way to plan:

1. Confirm your cat's current weight with your veterinarian.

2. Confirm the FIP type so you know the correct mg/kg dose (wet 6 mg/kg, dry 8 mg/kg, ocular 10 mg/kg, neurological 10 mg/kg for injectables).

3. Calculate the daily milligram dose with your vet.

4. Choose the GS-441524 strength that keeps the daily injection volume practical.

5. Multiply across the 84-day protocol to estimate how many vials the full course needs.

6. Add any veterinary visit, monitoring, or supportive care costs your clinic charges.

We do not publish a single flat total, because a fair estimate has to reflect your individual cat. We publish exact product prices and official dosing figures so you and your veterinarian can build an accurate plan.

What else should you budget for beyond the medication?

Beyond the GS-441524 medication itself, plan for veterinary consultations, diagnostic testing, and follow-up monitoring across the 84-day protocol. These clinical costs vary by clinic and region and are set by your veterinarian, not by the medication price.

Typical additional items to discuss with your clinic include:

• Initial diagnosis and confirmation of the FIP type.

• Bloodwork and monitoring during and after treatment.

• Any supportive or organ-support care your vet recommends as an optional adjunct.

• A post-treatment observation period to confirm remission.

Building these into your budget early helps avoid surprises and keeps the focus on completing the full course, which is central to a strong outcome.

FAQ

How much does FIP treatment cost for a cat in the US?

The medication cost depends on your cat's weight, FIP type, and the product chosen. At CureFIP, GS-441524 Antiviral Injectables range from $49.00 (15 mg/ml, 8ml) to $119.00 (40 mg/ml), and Cure FIP™ Oral Capsules are $129.00, with the standard course running 84 days under veterinary supervision.

Why does FIP type change the cost?

FIP type sets the daily dose in mg/kg. For GS-441524 injectables the dose is 6 mg/kg for wet, 8 mg/kg for dry, and 10 mg/kg for both ocular and neurological FIP, so the higher-dose forms use more medication per day across the 84-day protocol.

Is the injectable or the oral route more cost-effective?

The two routes are matched to different evidence and different FIP types, so they should be compared on suitability first. GS-441524 monotherapy injectables report a 92% success rate (UC Davis, Pedersen 2019) across all four types, while the dual antiviral oral capsules report 78.3% remission (Li and Cheah, 2025) and are positioned for wet and dry FIP. Your veterinarian will help you choose.

How long is the FIP treatment protocol?

A standard course runs 84 days (12 weeks) of daily treatment under veterinary supervision. GS-441524 injectables are given as 1 subcutaneous injection per day, 7 days a week, and Cure FIP™ Oral Capsules are 1 capsule per day for a recommended 12 weeks.

Can I estimate the total cost myself?

You can plan an estimate by combining your cat's daily dose with the product price across the 84-day course, but the exact daily dose depends on your cat's weight and FIP type, so it should be calculated with your veterinarian. We publish exact product prices and official dosing figures to make that planning accurate.