Best Treatment for FIP in Cats in Australia (2025)

The best treatment for Feline Infectious Peritonitis (FIP) in cats in Australia is antiviral therapy built around GS-441524, given every day for a full 84-day protocol under veterinary supervision. GS-441524 monotherapy has a 92% success rate reported by UC Davis (Pedersen, 2019), and it is the ingredient at the core of every CureFIP option. The right product for your cat depends on which of the four forms of FIP it has and whether your cat can take a daily injection or an oral capsule.

A cat resting comfortably at home.

What is the best treatment for FIP in cats in Australia?

The best treatment for FIP in Australia is a daily antiviral course of GS-441524 for 84 days, chosen to match the form of FIP your cat has and delivered with your veterinarian's guidance. GS-441524 is the proven hero of modern FIP treatment, with a 92% success rate reported by UC Davis (Pedersen, 2019) for injectable monotherapy.

FIP was once considered a fatal diagnosis. That changed with GS-441524, and more than 100,000 cats have been treated across the CureFIP network since 2019.

There is no single product that suits every cat. The decision comes down to the form of FIP, your cat's weight, and whether an injectable or an oral route is more practical for your household. We are clear about what the data shows and what it does not.

What is GS-441524 and why is it the core of FIP treatment?

GS-441524 is an antiviral nucleoside analogue that blocks the FIP virus from replicating, and it is the ingredient at the heart of every CureFIP treatment. Evidence shows a 92% success rate for GS-441524 injectable monotherapy in the UC Davis study (Pedersen, 2019).

A standard course runs 84 days (12 weeks) of daily dosing. Cats are then observed through a monitoring period, and many reach lasting remission.

Because GS-441524 works by stopping viral replication, consistency matters. Missing days or stopping early is one of the most common reasons treatment struggles, which is why the full protocol and veterinary supervision are essential. If you are just starting, our guide on what to expect during your cat's first week on GS-441524 treatment walks you through the early days.

What are the four forms of FIP and how do they change treatment?

FIP takes four forms, wet, dry, ocular, and neurological, and each shapes the treatment plan and the daily dose. Matching the dose to the form is one of the most important steps in getting treatment right, and your veterinarian confirms the diagnosis.

If you are still working out whether your cat's signs point to FIP, our complete guide to cat FIP symptoms explains what to look for, and it is worth reading alongside our article on common FIP misdiagnoses.

Wet (effusive) FIP

Wet FIP causes fluid to build up in the abdomen or chest, leading to a swollen belly or laboured breathing. For the GS-441524 injectable, the catalog dose for wet FIP is 6 mg/kg once daily. This is often the fastest form to show visible improvement once fluid begins to clear.

Dry (non-effusive) FIP

Dry FIP produces inflammatory masses in organs without the obvious fluid, so signs can be vaguer, such as weight loss, fever, and lethargy. For the GS-441524 injectable, the catalog dose for dry FIP is 8 mg/kg once daily.

Ocular FIP

Ocular FIP affects the eyes, causing colour changes, cloudiness, or inflammation inside the eye. For the GS-441524 injectable, the catalog dose for ocular FIP is 10 mg/kg once daily, because eye tissue needs a higher dose to reach.

Neurological FIP

Neurological FIP affects the brain and spinal cord, with signs such as wobbliness, seizures, or behavioural changes. For the GS-441524 injectable, the catalog dose for neurological FIP is 10 mg/kg once daily, reflecting the higher dose needed to cross into the nervous system.

Which CureFIP product is best for my cat?

The best CureFIP product depends on the form of FIP, your cat's weight, and whether you can give a daily subcutaneous injection or prefer an oral capsule. Injectables are dosed by form and body weight, while the oral dual-action capsules are dosed by weight band.

Here is how the antiviral FIP products compare, using figures exactly as listed in the Australian catalog.

Product	Strength / pack	Price (AUD)	Schedule
GS-441524 Antiviral Injectable	20 mg/ml, 8ml	AU$79.00	1 subcutaneous injection per day, 7 days/week, 84 days
GS-441524 Antiviral Injectables	30 mg/ml, 8ml	AU$99.00	1 subcutaneous injection per day, 7 days/week, 84 days
CureFIP Oral Capsules - Dual-Action Formula	Dual-action (GS-441524 + EIDD-1931)	AU$139.00	1 capsule per day, every day, 12 weeks

Both injectable strengths are available With B12 or Without B12. The 20 mg/ml and 30 mg/ml options let your veterinarian match concentration to your cat's dose and body weight so injection volumes stay comfortable.

Injectable dosing by FIP form

The GS-441524 injectables share the same dosing structure across both strengths. This four-row table mirrors the four forms of FIP above.

FIP form	Injectable dose	Schedule	Duration
Wet	6 mg/kg	1 SC injection/day	84 days
Dry	8 mg/kg	1 SC injection/day	84 days
Ocular	10 mg/kg	1 SC injection/day	84 days
Neurological	10 mg/kg	1 SC injection/day	84 days

Reference: Pedersen et al., UC Davis (PMC6435921).

Oral dual-action capsules by weight band

The CureFIP Oral Capsules - Dual-Action Formula combine GS-441524 and EIDD-1931 in one daily capsule, dosed by weight band rather than by form.

Weight band	Per capsule	Schedule
Under 2.5 kg	GS-441524 25 mg + EIDD-1931 5 mg	1 capsule per day
2.5 to 5 kg	GS-441524 35 mg + EIDD-1931 8 mg	1 capsule per day
Over 5 kg	GS-441524 50 mg + EIDD-1931 12 mg	1 capsule per day

The oral dual route is positioned for wet and dry FIP. Some regions note it is not recommended once ocular or neurological signs are present, or if the cat cannot eat or defecate. Your veterinarian is the right person to confirm whether an oral or injectable route suits your cat.

Many Australian and New Zealand caregivers are choosing the dual antiviral approach, and you can read more in our article on why vets and cat owners are choosing dual antiviral therapy for FIP.

What success rate can I expect from FIP treatment?

The reported outcomes depend on which protocol you use. GS-441524 injectable monotherapy has a 92% success rate reported by UC Davis (Pedersen, 2019), while the dual antiviral combination of GS-441524 and EIDD-1931 has a 78.3% remission figure reported by Li and Cheah (2025).

These two figures come from different studies and different protocols, so they should never be blended or averaged. When comparing providers, ask which stat matches which product, because a number only means something when it is attached to the right protocol.

Remission, not a promise of a fixed result, is the realistic and well-documented goal. Real outcomes vary with the form of FIP, how early treatment starts, and how consistently the protocol is followed.

How much does FIP treatment cost in Australia?

In Australia, CureFIP antiviral products start at AU$79.00 for the GS-441524 Antiviral Injectable (20 mg/ml, 8ml), AU$99.00 for the GS-441524 Antiviral Injectables (30 mg/ml, 8ml), and AU$139.00 for the CureFIP Oral Capsules - Dual-Action Formula. Total course cost depends on your cat's weight, the form of FIP, and the daily dose your veterinarian sets, since heavier cats and higher-dose forms use more product over 84 days.

Because dosing is per kilogram for injectables and per weight band for capsules, the best way to estimate a full course is to confirm your cat's current weight and diagnosed form with your veterinarian first. Our practical FIP survival strategies for Australian and New Zealand cat owners can help you plan for the weeks ahead.

How do I give the treatment and support recovery?

Giving FIP treatment well comes down to consistency, correct dosing, and good supportive care throughout the 84 days. Here is the general shape of a treatment journey, which your veterinarian will tailor.

1. Confirm the diagnosis and FIP form with your veterinarian.

2. Choose the injectable or oral route and the matching dose for your cat's weight.

3. Give the treatment at the same time each day for the full 84-day protocol.

4. Weigh your cat regularly, because doses are adjusted as weight changes.

5. Continue through the monitoring period after day 84 to confirm remission.

Appetite often improves as treatment takes hold, and steady eating supports recovery. For practical help, see our advice on appetite support and feeding a cat with FIP and our guide on how to support your cat's recovery after FIP treatment.

If signs return after treatment, do not panic. Our article on understanding FIP relapse explains why it happens and what steps to take with your veterinarian.

FAQ

What is the best treatment for FIP in cats in Australia?

The best treatment is a daily GS-441524 antiviral course given for the full 84-day protocol under veterinary supervision, with the product and dose matched to your cat's form of FIP. GS-441524 injectable monotherapy has a 92% success rate reported by UC Davis (Pedersen, 2019).

Is the injectable or the oral treatment better?

Both are built around GS-441524, so the choice depends on your cat and your household. Injectables are dosed by form and weight and suit all four forms, while the CureFIP Oral Capsules - Dual-Action Formula are positioned for wet and dry FIP and are dosed by weight band. Your veterinarian is the right person to confirm the route.

How long does FIP treatment take?

A standard course runs 84 days (12 weeks) of daily dosing, followed by a monitoring period to confirm remission. Stopping early is a common reason treatment struggles, so completing the full protocol matters.

What does FIP treatment cost in Australia?

CureFIP antiviral products in Australia start at AU$79.00 for the GS-441524 Antiviral Injectable (20 mg/ml, 8ml), AU$99.00 for the 30 mg/ml injectable, and AU$139.00 for the CureFIP Oral Capsules - Dual-Action Formula. Total cost over 84 days depends on your cat's weight and diagnosed form, so confirm the daily dose with your veterinarian.

Can neurological or ocular FIP be treated?

Yes. For the GS-441524 injectable, the catalog dose is 10 mg/kg once daily for both ocular and neurological FIP, reflecting the higher dose needed to reach the eyes and nervous system. The oral dual-action capsules are not recommended once ocular or neurological signs are present, so your veterinarian will guide the right approach.

If your cat has been diagnosed with FIP, the next step is to understand your options and get the right dose for your cat's weight and form. We are here to talk it through with you, and your own veterinarian remains your partner in every treatment decision. You can explore CureFIP treatment options for cats in Australia and New Zealand to learn more and reach our team.