Anti-nausea medications: quick, practical guide
Nausea wrecks your day fast. Good news: there are reliable medicines that work for motion sickness, pregnancy, surgery, and chemotherapy. This page explains common anti-nausea drugs, when each one makes sense, and simple safety tips so you can talk with your doctor or pharmacist like a pro.
How they work: anti-nausea drugs (antiemetics) act on different brain areas or the gut. Some block serotonin signals (ondansetron), some calm motion-sensing nerves (meclizine), some blunt dopamine signals (metoclopramide, prochlorperazine), and others work as sedating antihistamines (diphenhydramine, promethazine). Knowing the type helps match the med to the cause.
Common options you’ll see
Ondansetron (Zofran): often used after surgery or during chemo. Typical dose is 4–8 mg. Works fast and causes little drowsiness, but it can affect heart rhythm (QT prolongation) in some people—tell your doctor about heart disease or other medicines.
Promethazine (Phenergan): an older, effective choice for severe nausea. Typical oral dose is 12.5–25 mg. It sedates and can cause dizziness or blurred vision. Promethazine can be strong—avoid driving until you know how it affects you.
Metoclopramide (Reglan): helps when nausea comes from slow stomach emptying or certain migraines. Usual dose is 10 mg. Watch for muscle stiffness or restlessness; long-term use may cause movement problems, so use it short-term unless your doctor says otherwise.
Meclizine, dimenhydrinate: over-the-counter choices for motion sickness and vertigo. Meclizine 25–50 mg is taken before travel. They make many people sleepy—plan accordingly.
Who should be careful
Pregnancy: morning sickness often treats best with doxylamine plus vitamin B6 first. Some drugs are safe later in pregnancy, but always check with your OB before taking prescription antiemetics.
Children and older adults: dosing changes and side effects matter more. Older adults are more sensitive to sedation and falls. Kids can react differently—ask a pediatrician.
Interactions: many antiemetics add drowsiness when mixed with alcohol, opioids, or some antidepressants. Some affect heart rhythm. Tell your prescriber about all meds and supplements.
When to get urgent help: if nausea comes with severe belly pain, high fever, confusion, fainting, blood in vomit, or signs of dehydration (very low urine, dry mouth, dizziness), seek medical care right away.
Practical tips: match the drug to the cause (motion vs migraine vs chemotherapy). Start with OTC options for mild motion sickness. Use short courses for post-op or stomach bugs. If you’re buying online, stick to reputable pharmacies and keep prescriptions for controlled meds. For a focused guide on buying promethazine (Phenergan) safely online, check our dedicated article on that topic.
Want a quick plan? For travel use meclizine before you leave. For severe post-op nausea, ask about ondansetron. For persistent stomach-emptying problems, talk to your doctor about metoclopramide or other targeted treatments. And always ask about side effects and drug interactions—those two things matter most.
