8 Alternatives to Ondansetron: What Works When One Med Isn’t Enough

Nausea can wreck your day, your plans, and your mood. Even if Ondansetron usually does the trick, sometimes you need other tools in your kit—because not every kind of nausea responds the same way, and side effects can get old fast. Luckily, there are several real alternatives, each with their own quirks and strengths.

Depending on what's making you sick (think: surgery, pregnancy, cancer treatment, carsickness), some medications—or even natural options—might work even better than Ondansetron. In the end, you want quick, predictable relief without more trouble than it’s worth. In this article, I’m breaking down eight solid alternatives, from well-tested medications to stuff you can grab at the health store. We’ll look at what they do best, what they don’t, how easy they are to use, and what side effects might crop up.

Keep reading for the lowdown on each alternative. Don’t just cross your fingers and hope—find something that actually helps you keep your head clear and your stomach settled.

• Promethazine (Phenergan)
• Metoclopramide (Reglan)
• Prochlorperazine (Compazine)
• Dimenhydrinate (Dramamine)
• Meclizine (Antivert)
• Scopolamine (Transderm Scop)
• Ginger Supplements
• Cannabinoids
• Summary & Comparison Table

Promethazine (Phenergan)

If you’re struggling with nausea and Ondansetron alternatives are on your radar, Promethazine is a go-to for a lot of doctors. It’s been around for decades and shows up in ERs, travel kits, and even some home medicine cabinets. Promethazine is an antihistamine, but it also packs a punch against nausea, making it handy for everything from migraine flare-ups to motion sickness and even the kind of queasiness you get after anesthesia.

This med is flexible—you can take it as a tablet, liquid, suppository, or even as an injection. For really tough nausea when swallowing anything is out of the question, the rectal form (suppository) pretty much saves the day. It starts working in about 20 minutes and the effects can last a few hours, so you’re not constantly popping pills.

Pros

• Comes in multiple forms: easy to find as tablet, syrup, suppository, or by shot.
• Works well for a lot of causes—motion sickness, migraines, post-surgery, and more.
• Quick onset—typically relieves nausea in about 20 minutes.
• Anti-nausea plus sedative effects, which can help if you also need rest.

Cons

• Strong sedative effect: can make you really drowsy and even groggy the next day.
• Can cause dry mouth, blurry vision, and constipation.
• Not safe for kids under 2, and risky in older adults (confusion, falls).
• Shouldn’t combine with other sedatives (including alcohol).

If your nausea comes with severe vomiting or you just want relief without worrying what’s stronger than a ginger tea, Promethazine is worth asking your doctor about. Just go easy if you’re sensitive to meds that make you sleepy—or if you need to be up and alert for work, driving, or taking care of kids. Compared to Ondansetron, sedation and dry mouth are way more common, but for full-blown nausea, sometimes the tradeoff is worth it.

Metoclopramide (Reglan)

Here’s a Ondansetron alternative with a bit of a split personality—Metoclopramide isn’t just an anti-nausea medicine, it also helps the stomach empty faster. That means it’s helpful if your nausea is tied to slow digestion or gastroparesis, a common problem for folks with diabetes or those recovering from surgery.

Metoclopramide works on dopamine and serotonin receptors in the gut and brain, so it blocks nausea signals and gets things moving in your digestive tract. Compared to Ondansetron, you might notice it’s especially good if your nausea hits after eating or when you feel like food is just sitting there.

Pros

• Works fast (sometimes within 30 to 60 minutes).
• Multiple forms—can be taken as a pill, liquid, or even injection at the hospital.
• Reduces bloating and discomfort from slow stomach emptying.
• Approved for a wide range of causes—including migraine, chemotherapy, and reflux.

Cons

• Shouldn’t be used long-term (risk of movement problems like tardive dyskinesia if used over weeks to months).
• Possible side effects include drowsiness, restlessness, and rarely, twitchy muscles or painful spasms.
• Can interact with antidepressants and some pain meds.
• Not great for people with history of seizures or Parkinson's disease.

Docs usually suggest the lowest dose for the shortest possible time, just to avoid any neurological side effects. As always, tell your doctor about other meds—mixing things like SSRIs with Metoclopramide can up the risk of side effects.

If your nausea feels stubborn and you suspect it’s tied to slow digestion, Metoclopramide gives Ondansetron a real run for its money. Just keep an eye on side effects, and don’t make it your go-to every single day.

Prochlorperazine (Compazine)

If Ondansetron isn’t helping, Prochlorperazine—better known as Compazine—is a common backup. Doctors have been using it since the 1950s to tame nausea, especially when it comes from migraine, vertigo, or chemo. It’s part of a group called phenothiazines, and it works by blocking dopamine in the brain, which calms the area that triggers vomiting.

This isn’t just an old-school option. You can take Compazine as a pill, but you’ll also find it as a suppository or even by IV in the hospital, which can be super useful if you can’t keep anything down. One interesting stat: in a head-to-head trial for migraine-related nausea, Prochlorperazine worked just as well as Ondansetron—and sometimes faster for severe symptoms.

Pros

• Works fast for nausea tied to migraine, anxiety, or medication reactions.
• Comes in several forms—pill, suppository, and IV—good options if you’re vomiting a lot.
• Usually covered by insurance and pretty affordable at most pharmacies.

Cons

• Can cause drowsiness or make you feel zonked out; some people get restless or jittery.
• Prolonged use may trigger movement problems (twitching, tremors), especially in older adults.
• Not ideal if you have certain conditions, like Parkinson’s, because of how it messes with dopamine.

So, if you need a hardworking, no-nonsense medicine for tough nausea and migraine situations, Compazine is a tried and true alternative. Just be sure to watch for side effects and talk through any movement problems or medical conditions you already have with your doc. It’s a staple in the anti-nausea toolkit for a reason.

Dimenhydrinate (Dramamine)

If you’ve ever gotten carsick as a kid, someone probably handed you a Dramamine. Dimenhydrinate is an old-school choice for treating nausea remedies tied to motion sickness—boats, planes, wild car rides—you name it. It works by blocking the signals in your brain that trigger nausea and vomiting, making it a go-to for travelers.

You can find Dramamine everywhere—pharmacies, grocery stores, gas stations. It works pretty fast, usually kicking in within 30 minutes. You can use it for prevention (taking it before your trip) or as soon as you start to feel queasy. Doctors will sometimes suggest it for vertigo, too, but it’s mainly marketed for motion sickness. If you’re dealing with stomach-churning road trips, Dramamine often does the trick.

For adults, the typical dose is 50-100 mg every 4-6 hours (up to 400 mg in 24 hours). Kids can take it, but talk to their doctor about the right dose. People like it because it's cheap, widely available, and doesn’t need a prescription.

Pros

• Packed with travel—just toss it in your bag and go
• Works for most kinds of motion sickness
• Starts acting in about 30 minutes
• Can be used for adults and kids (age 2+ with medical guidance)
• Available over-the-counter—no need to visit your provider for a script

Cons

• Makes a lot of people drowsy—seriously, plan a nap
• Dry mouth and sometimes blurred vision
• Not great for using if you need to work, drive, or stay sharp
• Can trigger urinary retention, especially in older males
• May interact with other sedating meds or alcohol

If you look at one of the main reasons people switch off Ondansetron alternatives, it’s the drowsiness with meds like Dramamine. About 36% of users report feeling tired after a single dose, compared to much lower rates for some newer anti-nausea options:

Bottom line: Dimenhydrinate is a handy fix for travel or motion-based nausea remedies, just don’t expect to crush your workload or study for exams after taking it. If drowsiness bothers you, you might want to try something else.

Meclizine (Antivert)

If motion sickness or vertigo makes your life miserable, Meclizine (brand name Antivert) is a classic in the world of Ondansetron alternatives. It's a go-to for dizziness, nausea, and that awful feeling like everything's spinning—not just for road trips, but also for conditions like Meniere's disease or vestibular migraines.

Meclizine works by blocking signals in your brain that trigger vomiting and balance problems. It's taken as a tablet or chewable, usually an hour before travel if you're dealing with motion sickness. One perk: you don’t need to keep popping pills all day, since it works for around 24 hours, making it pretty convenient for a long flight or road trip.

Compared to Ondansetron, Meclizine doesn’t need a prescription in the US for mild uses, so you can grab it over the counter at most pharmacies. It won’t do much for nausea from chemo or major surgery, but when the issue is cars, boats, or even anxiety-related dizziness, it’s often all you need.

Pros

• Long acting—relief lasts up to a full day
• Affordable and easy to find without a prescription
• Chewable option for folks who can’t swallow pills
• Great for motion sickness and vertigo-related nausea

Cons

• Can make you sleepy or give you a dry mouth
• Not much help for nausea from chemo or strong medication
• Shouldn't be mixed with alcohol or used with certain anxiety meds (ask your pharmacist!)
• Sometimes not suitable for older adults because of fall risk from drowsiness

If you’re curious how Meclizine stacks up, check out these numbers from a CDC travel health guide:

Bottom line: if your nausea is linked to movement or dizziness, and you want something easy and reliable, Meclizine is worth a look before reaching for a prescription.

Scopolamine (Transderm Scop)

Ever get that brutal wave of nausea before a boat trip or long drive? Scopolamine, best known by the brand name Transderm Scop, is hands down one of the most reliable meds for motion sickness. It isn’t a pill—this one comes as a small patch you stick behind your ear. Because it delivers a steady dose through your skin, it’s all about slow, consistent relief, without that up-and-down effect you sometimes get from swallowing a tablet.

Scopolamine works by blocking signals in the brain that trigger nausea and vomiting. It’s especially useful if you know you’re at risk for motion sickness or if you’ve got a big trip coming up and you want all-day coverage. Pop the patch on about four hours before your trip; it’ll keep working for up to three days, making it a top pick for cruises, road trips, or even small plane rides.

You don’t have to remember to take pills, and because it isn’t hitting your gut directly, you skip a lot of the GI side effects that can come with other Ondansetron alternatives.

Pros

• Patch lasts up to 72 hours—great for longer trips
• Avoids stomach upset since it’s absorbed through the skin
• No need to take pills or bother with complicated dosing schedules
• Consistent delivery helps prevent breakthrough nausea

Cons

• Some people get skin irritation at the patch site
• Can cause dry mouth, blurry vision, or drowsiness (so don’t drive until you know how you react)
• Patching needs a little prep—won’t help if you’re already feeling sick
• Not ideal for kids, or anyone with glaucoma or certain medical conditions

There was a 2022 review that found scopolamine cut the risk of motion sickness by more than half compared to placebo. One fun tip: folks who use the patch for cruises say it makes a world of difference, but just don’t touch your eyes after handling it, or you’ll feel the sting. If you travel a lot or get motion sick easily, scopolamine’s long-acting patch is worth asking your doctor about.

Ginger Supplements

When you think natural nausea remedies, ginger almost always pops up first. Some folks swear by ginger tea or hard candies, but supplements pack a much bigger punch and are way more convenient. Capsules, chewables, and even liquid extracts show up in health food aisles and pharmacies everywhere, and there's legit science backing ginger for certain types of queasiness.

If you get motion sickness or struggle with pregnancy-related nausea, ginger is one of the most-studied herbal options. There’s solid evidence showing ginger can cut down on both the intensity and frequency of nausea—especially for mild and moderate cases. In one study on patients dealing with morning sickness, ginger worked better than placebo and came close to matching prescription meds for relief. Some evidence even suggests it may help after surgery or during chemo, though results aren’t always as strong as traditional drugs like Ondansetron or dimenhydrinate.

How much do you take? Most studies use 250mg to 1000mg a day, split into 2 or 3 doses. Ginger root capsules and tablets are super easy to find, and you can adjust the dose based on how much you actually need. If you want to go the whole food route, 1/2 to 1 teaspoon of fresh ginger grated into water or tea can be surprisingly effective too.

Ginger’s biggest selling point: hardly any side effects at normal doses. Some people get mild heartburn or an upset stomach, but it’s nowhere near as risky as prescription anti-nausea treatments. Plus, it’s totally over-the-counter. Just make sure to talk to your doctor if you’re pregnant, on blood thinners, or take medication for heart issues, because ginger can thin the blood slightly and might affect some meds.

Tip: Not all ginger supplements are legit—look for ones with real ginger root extract, and skip things that are basically just ginger-flavored candy. Aim for brands that show exact dosages and have some quality certification. If you want to avoid more pills, consider ginger chews or tea before car rides or flights. No fuss, no prescription needed.

Cannabinoids

You might not think of cannabis right away when looking for Ondansetron alternatives, but cannabinoids—mostly THC and CBD—are definitely in the running. Doctors sometimes recommend certain cannabis-based medicines to handle strong or stubborn nausea, especially for patients stuck in the cycle of chemo-related sickness.

Drugs like dronabinol (basically a lab-made THC) and nabilone have FDA approval for nausea related to chemotherapy when nothing else works. These aren’t the same thing you snag from a dispensary, but they act on your body’s own endocannabinoid system to dull the urge to vomit. That’s a huge deal when everything else fails.

For regular folks dealing with nausea, people sometimes try medical cannabis or even CBD oils. The research is hit and miss—CBD doesn’t have court-proven results for nausea, but THC definitely squashes the urge for some users. The downside? THC can make you high, and some people risk anxiety or feeling spaced out. Plus, the legal status for non-prescription cannabinoid products changes wildly depending on your state or country.

A 2021 Canadian survey found that about 30% of medical cannabis users rely on it for nausea—and most of those folks said they felt some degree of relief. Not perfect science, but it's an honest peek into how people handle tough cases.

Pros

• Really good when other anti-nausea treatments don’t work, especially with chemo.
• Multiple ways to use: capsule, oil, edible, sometimes inhaled forms.
• Some people feel the effect fast, especially with THC-containing meds.
• May also help with improving appetite.

Cons

• THC can spark anxiety, drowsiness, or trouble with focus.
• Can be illegal or tightly regulated, depending where you are.
• Insurance usually doesn't cover non-prescription blends.
• Not much research for stuff like regular nausea or motion sickness.
• Feeling high or dizzy is common if you’re sensitive to THC.

Summary & Comparison Table

Feeling queasy and not sure which anti-nausea fix to try first? Here’s how the Ondansetron alternatives stack up so you don’t get lost in pharmacy jargon. Everyone’s body reacts differently, so what settles my stomach might mess with yours. The big goal is to find the most effective nausea remedy that fits your life—without too many annoying side effects.

You’ll notice that some options, like Scopolamine patches or ginger supplements, work better for motion or morning sickness, while strong meds like Prochlorperazine can be a lifesaver for chemo or migraine-related nausea. Others—like cannabinoids—are only recommended if standard treatments don’t work, and they’re not legal everywhere.

If you’re making a quick decision, check out this comparison table. It covers how the meds are used, what makes them stand out, and real-life things to watch for:

If you want something simple and over-the-counter, ginger supplements or meclizine might be your first stop. Need stronger backup for chemo or tough cases? Talk to your doctor about Prochlorperazine or Metoclopramide. For long boat rides or road trips, Scopolamine patches really shine—they’re discreet and last for days, but can bug your skin if you sweat or swim a lot.

• Always double-check for interactions—don’t mix these meds unless your doctor says it’s cool.
• For kids or during pregnancy, ask straight away before grabbing anything off the shelf.
• If you’re trying natural options like ginger, go for trusted brands—cheap ones aren’t always pure.

Got tough nausea that won’t quit? Sometimes you need to rotate through different anti-nausea treatments until you find what really sticks. Talk with your doctor if you’re struggling—there’s almost always another option to try.