Nimodipine: What It Does and How to Use It Safely

If you or a loved one is recovering from a subarachnoid hemorrhage (bleeding around the brain), nimodipine is a drug you’ll likely hear about. It’s a calcium channel blocker prescribed to lower the chance of delayed brain damage caused by blood-vessel spasms after that type of bleeding. Here’s a plain, useful look at what nimodipine does and how to handle it in real life.

How nimodipine works and when it’s used

Nimodipine relaxes small arteries in the brain, which helps prevent or reduce vasospasm — the tightening of blood vessels that can cut blood flow after a subarachnoid bleed. Hospitals give nimodipine as part of the standard care after confirmed subarachnoid hemorrhage to help protect brain function. It’s not a general treatment for high blood pressure or chest pain like other calcium channel blockers — its main role is neuroprotection in this specific setting.

Dosing, side effects and safety tips

Most commonly, adults take 60 mg by mouth every 4 hours for up to 21 days. Start timing and dose exactly as the treating team prescribes. Some hospitals use an oral solution when patients can’t swallow capsules. Don’t try to give capsules intravenously — that’s dangerous. Follow your care team’s instructions for feeding tube administration if needed.

Watch your blood pressure. The most common side effect is low blood pressure (hypotension). You may also feel lightheaded, dizzy, flushed, or nauseous. If you become faint, weak, or unusually tired, tell staff right away. Nimodipine can slow the heart rate in some people, so clinicians often monitor blood pressure and pulse while you’re on it.

Drug interactions matter. Nimodipine is broken down by the liver enzyme CYP3A4. Strong CYP3A4 inhibitors such as ketoconazole, certain macrolide antibiotics (like erythromycin), and grapefruit juice can raise nimodipine levels and increase the risk of low blood pressure. Enzyme inducers (like rifampin or some seizure medicines) can lower its effect. Always tell your medical team about every medicine and supplement you take.

Pregnancy and breastfeeding: data are limited. If you’re pregnant or breastfeeding, the team will weigh risks and benefits carefully. For most patients after acute brain bleeding, the immediate need to reduce vasospasm guides the decision.

Practical tips: take the drug on schedule, keep a simple log if you’re managing doses at home, avoid grapefruit and check with clinicians before starting or stopping other meds, and report fainting or sudden drops in blood pressure immediately. If you have questions about how to give nimodipine through a feeding tube or about switching formulations, ask your nurse or pharmacist — they’ll give step-by-step instructions tailored to your situation.

Nimodipine can make a real difference after a subarachnoid hemorrhage, but it needs careful use. Stay in touch with your medical team, and don’t hesitate to ask for clear instructions about dosing, side effects, and drug interactions.