Pregabalin for Cats: 5 mg/kg, 1.5 Hours Before Travel

The first FDA-approved drug for a cat that panics in the car is not a classic sedative. It is pregabalin oral solution, dosed at 5 mg/kg (0.1 mL/kg) about 1.5 hours before the carrier goes out the door, and it is licensed for exactly two situations: transportation and the veterinary visit. In the field study behind the approval, 83 of 108 treated cats (77%) improved between two visits, against 46 of 101 cats (46%) on placebo.

What the approval actually covers

Bonqat, a 50 mg/mL pregabalin oral solution, was approved under NADA 141-580 on 17 November 2023 and is the first FDA-approved animal drug containing pregabalin. The label is deliberately narrow: alleviation of acute anxiety and fear linked to transportation and veterinary visits, one dose of 5 mg/kg roughly 1.5 hours before the event, and a maximum of two consecutive days. It is a DEA Schedule V controlled substance, sold only on prescription, in a 2 mL bottle with a 1 mL dosing syringe. Nothing on that label covers thunderstorms, fireworks, separation or a cat that hides all day.

The field study in two numbers

Two hundred and thirty-eight cats with a documented history of fear in cars and clinics were split into three groups: 108 at 5 mg/kg, 29 at 2.5 mg/kg and 101 on placebo, with two visits 5 to 10 days apart. A little over half of the treated cats scored good to excellent on both the car trip and the examination, against about one third of the placebo cats. Improvement across both exams was 77% versus 46%. Reported reactions were mild sedation, ataxia and lethargy rather than the flat, unreachable cat that acepromazine can produce.

Why a liquid peaks in 30 minutes and a capsule takes 3 hours

At 5 mg/kg in fasted cats the solution reached a peak plasma concentration of 10.1 µg/mL at 0.5 to 1.0 hours, with 94.3% absolute oral bioavailability. A Cornell study of 4 mg/kg pregabalin capsules in six cats peaked at 8.3 µg/mL, but only at 2.9 hours, with a half-life of 10.4 hours and moderate sedation in four of the six. That two-hour gap is the practical difference between dosing in the clinic parking lot and dosing before you put your shoes on. Dosage timing, not dose size, is where most home attempts fail.

Pregabalin, gabapentin, or neither

Both drugs bind the same calcium-channel subunit and both cause ataxia; pregabalin binds it with higher affinity. The difference that matters at 7 a.m. is kinetics.

Measure	Pregabalin solution, 5 mg/kg	Pregabalin capsule, 4 mg/kg	Gabapentin, oral
Time to peak	0.5 to 1.0 hours	2.9 hours	1 to 2 hours
Half-life in cats	Not stated on the label	10.4 hours	About 3 hours (177 minutes)
Licensed in cats for travel fear	Yes	No	No
Controlled status	Schedule V	Schedule V	Not scheduled in most states

The half-life column explains the after-visit problem. A gabapentin cat is often wobbly for 6 to 8 hours and still unsteady at dinner; a pregabalin cat dosed once at 8 a.m. is usually walking normally by late afternoon, which is why owners ask whether the return trip is safe. It is, on the label's own terms, provided it is day one or two.

Dose by weight, and the 1 mL ceiling

2.5 kg: 12.5 mg = 0.25 mL
3.5 kg: 17.5 mg = 0.35 mL
4.5 kg: 22.5 mg = 0.45 mL
6 kg: 30 mg = 0.6 mL
Over 10 kg (22 lb): the syringe holds 1 mL, so the label requires the total to be split into two doses

A 2 mL bottle therefore holds five trips for a 4 kg cat. Retail in the UK sits near £40 per bottle, roughly £8 a visit, against pennies per gabapentin capsule. Keep the bottle at 2 to 8 °C, use it within six months of opening, and note that up to one month of that storage can be at room temperature, not the whole six.

What can go wrong on the first dose

In target-animal safety studies, slight to severe hypersalivation appeared in every dose group immediately after dosing, so a cat that foams at the mouth for a minute is not necessarily overdosed. At 5 and 10 mg/kg systolic blood pressure fell significantly in a crossover trial of eight cats, while pulse and respiratory rate barely moved. That matters for a cat with heart disease or on blood-pressure medication, and it is the reason a vet rather than a web page sets the dose. Do not stack it with other sedatives, keep the cat in a secured carrier rather than loose in the car, and do not leave a wobbly cat on a counter or a balcony rail.

Trial it a week early, not on the morning

Give the first dose on an ordinary day at home, with nothing scheduled, and watch for three hours. In the same crossover study, sedation scores rose significantly from 150 minutes at 2.5 and 5 mg/kg, later than the plasma peak, so a cat can look normal at minute 60 and be unsteady at minute 150. Film 30 seconds of walking before and after. If the cat cannot walk a straight line, the vet can drop to 2.5 mg/kg, a dose that also produced measurable sedation without the deeper ataxia. A dry run also tells you whether the cat will swallow 0.4 mL of bitter liquid at all.

When the problem is not anxiety

Drooling and vomiting within minutes of moving off are motion sickness, not fear, and pregabalin does not treat it. Pain, nausea, high blood pressure, untreated hyperthyroidism and failing vision all produce a cat that yowls in the car and freezes on the table. The two-consecutive-day limit is also a signal: a cat that needs calming every day needs a behaviour plan and possibly a daily medication chosen for that purpose, not a travel drug used off-label. This article does not replace veterinary diagnosis; a prescription, an examination and a weight on the scale come first, and a cat that collapses, breathes slowly or cannot stand after a dose needs a call to the clinic, not a second dose.

Frequently asked

Can I use a human Lyrica capsule instead of the veterinary liquid?

Only under a prescription written for your cat. Capsules in the Cornell study of 4 mg/kg peaked at 2.9 hours rather than 0.5 to 1.0 hours, which changes your departure time, and a 25 mg capsule cannot be split accurately for a 4 kg cat that needs 20 mg. Pregabalin is a Schedule V controlled substance in the US, so the dose has to come from a vet who has weighed the cat.

How long does one dose last, and can I give a second one?

The label allows one dose of 5 mg/kg per event, on a maximum of two consecutive days. Capsule data give a half-life of about 10.4 hours in cats, so a single morning dose still leaves measurable drug in the evening; that is why a repeat dose on the same day is not in the instructions and should not be improvised.

The cat is wobbly and quiet after the dose. Is that an emergency?

Mild ataxia, sedation and lethargy are the reactions listed at approval, and hypersalivation right after dosing appeared in every dose group of the safety studies. Call the clinic the same day if the cat cannot stand or walk, breathes slowly, feels cold, vomits repeatedly, or is still unsteady more than 12 hours after the dose.