ondansetron

How long does Ondansetron stay in your body?

The elimination half-life of ondansetron is about 3 to 5 hours (roughly 4 hours) in healthy adults — the time it takes the body to clear about half of it. As a rule of thumb, a medicine is mostly gone after roughly 4 to 5 half-lives, though this varies from person to person with age and kidney or liver function. Not a prodrug. Ondansetron has some nonconjugated metabolites with pharmacologic activity, but the label states they are not present in plasma at concentrations likely to significantly contribute to its effect, so no active metabolite meaningfully outlasts the parent. Half-life lengthens with age (increase seen in patients over 75, to roughly 5-6 hours) and especially with liver disease: mean half-life rises to about 11.6 hours in mild-to-moderate hepatic impairment and to about 20 hours in severe hepatic impairment (Child-Pugh 10+). In severe renal impairment (CrCl under 30 mL/min) mean plasma clearance falls about 50%, though the label gives no specific half-life. Rule of thumb: it takes roughly 4-5 half-lives (about a day in a healthy adult) to clear the drug from the body.

This is general information, not medical advice. It doesn’t tell you when a drug test would read negative (tests detect substances for different, often longer, windows) or when it’s safe to take another dose — ask your pharmacist or prescriber. Source: Ondansetron hydrochloride tablet, film coated — FDA label (DailyMed), Clinical Pharmacology / Pharmacokinetics.

Frequently asked questions

What does Ondansetron treat?

Ondansetron (Ondansetron) may be used to treat alcoholism, based on NIH RxClass drug-classification data (conditions a drug may treat — not a verbatim copy of the FDA-approved label). This is general reference, not medical advice.

How is Ondansetron rated?

pharmaranks gives Ondansetron a composite score of 2.8 out of 5, currently based on 1 weighted source (FDA regulatory recall-safety data weighted highest). See our methodology at /how-we-rate.

How much does Ondansetron cost?

Nobody can tell you what you will pay — your price is set by your insurer's formulary, your deductible and the pharmacy's markup, and none of those are published. What IS published is what the pharmacy paid to acquire it: about $0.15 per ml, per the CMS NADAC survey. Treat that as the floor, not the quote — ask the pharmacist for the cash price as well as your copay, because for cheap generics the cash price often wins.

Is there a coupon or discount for Ondansetron?

pharmaranks is an independent ratings site, not a pharmacy — we don't issue coupons or sell Ondansetron. To pay less, Ondansetron is already a generic — usually the lowest-cost version — so the main levers are comparing cash prices between pharmacies and using a pharmacy discount-card service. Prices vary by pharmacy, insurance, and location, so always confirm at the counter. This is general reference, not medical or financial advice.

Who makes Ondansetron?

Ondansetron is marketed by Teva. You can see Teva's full profile, rating, and other products on pharmaranks.

Is Ondansetron a brand-name or generic drug?

Ondansetron is a generic medication; its active ingredient is Ondansetron. Generics contain the same active ingredient as the brand-name original and are usually lower cost.

Is Ondansetron available over the counter?

No. Ondansetron is a prescription (Rx) medication in the US — you need a prescription from a licensed clinician (in person or via telehealth); it isn't sold over the counter. For some conditions there are OTC alternatives — ask your pharmacist.

What forms does Ondansetron come in?

Ondansetron is currently marketed as injectable, solution, tablet and tablet, orally disintegrating, per the FDA's National Drug Code Directory.

What class of drug is Ondansetron?

Ondansetron is classified as serotonin-3 receptor antagonist, per the FDA's Established Pharmacologic Class.

Is Ondansetron FDA-registered?

Ondansetron is on record with the U.S. FDA under application number ANDA076810. You can verify this on its official FDA label.

Has Ondansetron been recalled by the FDA?

Ondansetron has no FDA recalls recorded under its own application in the openFDA enforcement database. Its recall-safety score reflects its manufacturer's overall recall record. This is general reference, not medical advice — check the FDA recall database for the latest alerts.

Is Ondansetron safe?

There's no single safe-or-not verdict. pharmaranks gives Ondansetron a recall-safety score of 56/100, based on its FDA recall history (no recalls under its own FDA application) — not an efficacy or side-effect rating. Review its FDA-label side effects and warnings before use, and always consult a licensed professional.