Prilosec (omeprazole): what it does and when to use it

Prilosec is a proton pump inhibitor (PPI) sold under the generic name omeprazole. It cuts stomach acid production, so people use it for acid reflux, GERD, stomach ulcers, and related heartburn. You can find low-dose omeprazole over the counter, but higher or long-term doses are prescription-only. Follow label directions or your doctor’s orders — don’t guess on your own.

How to take Prilosec

Take Prilosec before a meal, ideally 30–60 minutes before breakfast. That timing helps the drug work when acid production ramps up. Swallow the capsule whole; don’t crush delayed-release tablets. For occasional heartburn people often use a 14-day OTC course — read the package. If symptoms keep coming back or are severe, make an appointment with your doctor. Long-term use needs medical supervision and sometimes testing.

If your doctor prescribes it, follow the exact dose and length they give you. Don’t stop suddenly if you’ve taken it for months without checking first — rebound acid can make symptoms worse. Ask your clinician how and when to taper if they want you off it.

Side effects, risks and interactions

Most people tolerate Prilosec well. Common short-term side effects include headache, nausea, gas, and mild stomach pain. Serious reactions are rare, but if you notice signs of an allergic reaction (rash, swelling, trouble breathing) get medical help right away.

Longer use of PPIs can raise the risk of low magnesium, lower B12 absorption, and slightly higher chances of bone fractures in older adults. Your doctor may check magnesium or B12 if you stay on a PPI for months or years. People with liver disease need careful dosing, so mention liver problems to your clinician.

Prilosec can interact with other drugs. Notable examples: it may reduce the effect of clopidogrel and change blood levels of certain antifungals, HIV drugs, and some heart medicines. If you take blood thinners, heart meds, or specialized treatments, tell your prescriber and pharmacist before starting Prilosec.

Practical tips: avoid mixing alcohol with reflux triggers, sleep with your head raised if nighttime reflux is an issue, and avoid meals that reliably cause heartburn. If lifestyle changes don’t help, medication like Prilosec might. For questions about alcohol and reflux while on acid meds, see our GERD and Alcohol guide on the site.

Final note: Prilosec helps a lot of people, but it’s not risk-free. Use the lowest effective dose for the shortest time needed, keep your clinician informed about other drugs you take, and ask for a plan if you need long-term treatment.