Anti-Nausea Medication Selector
Use this tool to determine which anti-nausea medication might be best for your condition based on key factors.
Reglan (generic name Metoclopramide) is a dopamine‑receptor antagonist used to treat nausea, vomiting, and delayed stomach emptying. It comes in tablets, oral syrup, and injectable form.
Reglan is often prescribed when other anti‑nausea drugs haven’t helped, but it carries a unique side‑effect profile that makes many patients look for alternatives.
Why people consider other options
If you’ve been warned about tremors, drowsiness, or the rare risk of tardive dyskinesia, you’re not alone. Those concerns push doctors and patients toward drugs that work the same way without the same nervous‑system warnings. Below we break down the most common substitutes, what they do, and when they shine.
Quick look at the top alternatives
- Domperidone - a peripheral dopamine blocker that stays out of the brain, reducing movement‑related side effects.
- Ondansetron - a serotonin‑5‑HT3 antagonist famous for chemotherapy‑induced nausea control.
- Prochlorperazine - a phenothiazine anti‑psychotic that also calms severe nausea and vertigo.
- Promethazine - an antihistamine with strong anti‑emetic and sedative qualities.
- Erythromycin - a macrolide antibiotic that, at low doses, acts as a pro‑kinetic by stimulating motilin receptors.
- Cisapride - a serotonin‑4 agonist that enhances gastric motility; withdrawn in many countries but still available in limited, compassionate‑use programs.
How the drugs compare
| Drug | Primary Mechanism | Typical Uses | Common Dose | Key Side Effects | Prescription Status |
|---|---|---|---|---|---|
| Reglan (Metoclopramide) | Dopamine D2 receptor antagonist (central & peripheral) | Nausea, vomiting, gastroparesis, migraine headache | 10‑15mg orally 3‑4times daily | Tremor, drowsiness, ↑ prolactin, tardive dyskinesia (rare) | Prescription only |
| Domperidone | Peripheral dopamine D2 antagonist (no CNS penetration) | Gastroparesis, reflux, nausea | 10‑20mg orally before meals | Headache, dry mouth, QT prolongation (high doses) | Prescription (OTC in some EU countries) |
| Ondansetron | 5‑HT3 serotonin receptor antagonist | Chemo‑induced nausea, post‑op nausea, hyperemesis gravidarum | 4‑8mg orally or IV once daily | Constipation, headache, rare QT prolongation | Prescription |
| Prochlorperazine | Phenothiazine dopamine antagonist | Severe nausea, vertigo, psychosis (off‑label) | 5‑10mg orally 3‑4times daily | Sedation, extrapyramidal symptoms, low blood pressure | Prescription |
| Promethazine | H1 antihistamine with anti‑serotonin activity | Motion sickness, nausea, allergic reactions, sedation | 12.5‑25mg orally 2‑3times daily | Severe drowsiness, anticholinergic effects, respiratory depression (children) | Prescription (OTC in limited strengths) |
| Erythromycin (low‑dose) | Motilin receptor agonist (pro‑kinetic effect) | Gastroparesis, functional dyspepsia | 250mg orally 4times daily | Abdominal cramps, diarrhea, antibiotic resistance risk | Prescription (sometimes compounded) |
| Cisapride | Serotonin‑4 (5‑HT4) agonist | Severe refractory gastroparesis | 5‑10mg orally 3times daily | QT prolongation, arrhythmia (why it was withdrawn) | Restricted/compassionate‑use only |
Choosing the right drug for your situation
Here’s a quick decision‑tree you can run through with your doctor:
- Is the problem mainly nausea/vomiting? If so, ondansetron or prochlorperazine often give faster relief with fewer movement‑related side effects.
- Do you have delayed stomach emptying (gastroparesis)? Domperidone or low‑dose erythromycin are usually first‑line because they act peripherally.
- Are you sensitive to sedation? Avoid promethazine and prochlorperazine; consider ondansetron or a lower dose of metoclopramide for short‑term use.
- History of heart rhythm issues? Skip cisapride and high‑dose domperidone; stick with ondansetron (monitor QT) or metoclopramide (short courses only).
- Need a medication safe in pregnancy? Ondansetron is widely used for hyperemesis gravidarum; metoclopramide is also considered relatively safe but watch for extrapyramidal symptoms.
Always discuss these points with a healthcare professional. The best choice balances how well the drug works for you against the side‑effect risk you’re willing to accept.
Common myths and facts
- Myth: All anti‑nausea pills work the same way.
Fact: Each class targets a different receptor - dopamine, serotonin, histamine or motilin - so effectiveness varies by cause. - Myth: Metoclopramide is dangerous for everyone.
Fact: Serious movement disorders are rare (<0.5%); risk rises with treatment longer than 12days. - Myth: OTC antihistamines are enough for severe nausea.
Fact: They can help mild motion sickness but often fall short for chemotherapy‑induced or gastroparesis‑related nausea.
Practical tips for taking these medications safely
- Take the dose with a glass of water; many work best on an empty stomach (except erythromycin, which should be taken with food to reduce cramps).
- Set a reminder if you need to space doses evenly - missed doses can cause rebound nausea.
- Report any new tremor, involuntary movements, or rapid heartbeat to your doctor immediately.
- Never mix sedating anti‑emetics (like promethazine) with alcohol or strong CNS depressants.
- If you’re on a heart‑monitoring program, ask for a baseline ECG before starting cisapride or high‑dose domperidone.
When to see a doctor
Seek medical advice if you experience any of the following while on these drugs:
- Uncontrollable muscle twitches or facial grimacing (possible early sign of tardive dyskinesia).
- Chest pain, palpitations, or fainting - could signal arrhythmia.
- Severe constipation or inability to pass gas for more than 48hours.
- Allergic reaction: rash, swelling, or difficulty breathing.
Early intervention can prevent complications and allow a switch to a safer alternative.
Frequently Asked Questions
Can I use Domperidone instead of Metoclopramide for gastroparesis?
Yes, many clinicians start with domperidone because it stays out of the brain, lowering the chance of tremors or tardive dyskinesia. However, it may need ECG monitoring for QT prolongation, especially at higher doses.
Is Ondansetron safe during pregnancy?
Ondansetron is classified as Category B in the UK, meaning animal studies show no risk and limited human data are reassuring. It’s often the go‑to drug for severe morning sickness when other options fail.
What should I do if I develop a tremor on Metoclopramide?
Stop the medication immediately and contact your doctor. A short taper may be recommended, and the clinician might switch you to domperidone or a serotonin‑based anti‑emetic.
Why is Cisapride no longer sold over the counter?
Cisapride was linked to serious heart rhythm disturbances (QT prolongation) that could trigger fatal arrhythmias. It remains available only through special compassionate‑use programs for patients who have no other options.
Can I combine Promethazine with a sleep aid?
Both drugs cause sedation, so mixing them can lead to excessive drowsiness or respiratory depression, especially in the elderly. It’s best to avoid the combo unless a doctor explicitly advises it.