calan sr

How long does Verapamil Hydrochloride stay in your body?

The elimination half-life of verapamil hydrochloride is about 2.8 to 7.4 hours after a single dose, rising to about 4.5 to 12 hours with repeated dosing — 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. The oral label reports a mean ELIMINATION half-life of 2.8-7.4 hours in single-dose studies, which lengthens to 4.5-12 hours after repeated dosing (fewer than 10 consecutive doses given 6 hours apart), and says the half-life may increase further during dose titration - so the steady-state figure, not the single-dose one, is the realistic number for anyone actually taking it. The IV label describes two-phase elimination: a rapid distribution phase of about 4 minutes and a TERMINAL elimination phase of 2 to 5 hours; the terminal phase is the one quoted here. ACTIVE METABOLITE: verapamil is extensively metabolized by the liver, and one metabolite, norverapamil, is pharmacologically active - it has roughly 20% of verapamil's cardiovascular activity and can reach steady-state plasma concentrations about equal to verapamil's own. The label does not state norverapamil's half-life, so no number is given here. LIVER IMPAIRMENT: in hepatic insufficiency, metabolism is delayed and the elimination half-life is prolonged to about 14 to 16 hours, with plasma clearance falling to roughly 30% of normal. OLDER ADULTS: the label states aging may affect verapamil's pharmacokinetics and the elimination half-life may be prolonged in the elderly, without giving a figure. The label does not describe a kidney-impairment half-life change (only ~3-4% is excreted unchanged). Verapamil is not a prodrug. These are pharmacokinetic values from the label, not a drug-test detection window and not dosing guidance.

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: Verapamil Hydrochloride Tablets, Film Coated - FDA label (DailyMed), Clinical Pharmacology: Pharmacokinetics and metabolism.

Frequently asked questions

What does Calan SR treat?

Calan SR (Verapamil Hydrochloride) may be used to treat variant angina pectoris, atrial fibrillation, atrial flutter, hypertension, myocardial infarction, supraventricular tachycardia, 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 does Calan SR work?

Calan SR is a calcium channel blocker. Calcium channel blockers slow the flow of calcium into the muscle cells of the heart and blood vessels. With less calcium, blood vessels relax and widen and the heart pumps with less force, which lowers blood pressure and eases chest pain.

How is Calan SR rated?

pharmaranks gives Calan SR a composite score of 3.2 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 Calan SR 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 $5.71 for 30, 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. Pharmacies pay less for a same-class option, Amlodipine Besylate — about $0.33 on the same basis.

Is there a coupon or discount for Calan SR?

pharmaranks is an independent ratings site, not a pharmacy — we don't issue coupons or sell Calan SR. To pay less, ask your prescriber or pharmacist whether a generic equivalent exists, check the manufacturer's copay/savings card and patient-assistance program, and compare a pharmacy discount card against your insurance copay. Prices vary by pharmacy, insurance, and location, so always confirm at the counter. This is general reference, not medical or financial advice.

Who makes Calan SR?

Calan SR is marketed by Pfizer. You can see Pfizer's full profile, rating, and other products on pharmaranks.

Is Calan SR a brand-name or generic drug?

Calan SR is a brand-name product with the active ingredient Verapamil Hydrochloride. Lower-cost generic equivalents containing Verapamil Hydrochloride are available — ask your pharmacist.

Is Calan SR available over the counter?

No. Calan SR 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 Calan SR come in?

Calan SR is currently marketed as tablet, extended release, per the FDA's National Drug Code Directory.

What class of drug is Calan SR?

Calan SR is classified as calcium channel blocker, per the FDA's Established Pharmacologic Class.

Is Calan SR FDA-registered?

Calan SR is on record with the U.S. FDA under application number NDA019152. You can verify this on its official FDA label.

Has Calan SR been recalled by the FDA?

Calan SR 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 Calan SR safe?

There's no single safe-or-not verdict. pharmaranks gives Calan SR a recall-safety score of 64/100, 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.