Metoclopramide
Metoclopramide hydrochloride
Brand names:Reglan, Maxolon
A dopamine D2 antagonist with both antiemetic and prokinetic properties. Metoclopramide is used for refractory nausea and vomiting, gastroparesis, and migraine-associated nausea. Carries an FDA boxed warning for tardive dyskinesia with prolonged use and a high incidence of extrapyramidal effects including akathisia. Not first-line for routine tactical antiemetic needs - ondansetron is preferred.
Pharmacology and Actions
Metoclopramide produces antiemetic effect through central D2 receptor antagonism in the chemoreceptor trigger zone. The prokinetic effect comes from peripheral cholinergic enhancement, which increases lower esophageal sphincter tone, accelerates gastric emptying, and increases small bowel transit. Some 5-HT3 antagonism occurs at higher doses. Crosses the blood-brain barrier, which is responsible for both the antiemetic efficacy and the extrapyramidal side effect profile.
Indications
- Nausea and vomiting (chemotherapy-induced, postoperative, gastroparesis-related)
- Diabetic gastroparesis
- GERD refractory to other therapy
- Migraine-associated nausea and vomiting
- Adjunct for radiographic procedures requiring gastric emptying
Absolute Contraindications
- Known hypersensitivity to metoclopramide
- GI obstruction, perforation, or hemorrhage
- Pheochromocytoma (hypertensive crisis risk)
- Seizure disorder (lowers seizure threshold)
- Concurrent typical antipsychotics (additive extrapyramidal risk)
- History of tardive dyskinesia or neuroleptic malignant syndrome
Precautions and Side Effects
FDA boxed warning: tardive dyskinesia with prolonged use (over 12 weeks), often irreversible. Common: drowsiness, restlessness, fatigue. Extrapyramidal effects: acute dystonia (especially in young adults and children), akathisia (intense restlessness, often mistaken for worsening illness), parkinsonism. Cardiovascular: hypotension, bradycardia, QT prolongation. Endocrine: hyperprolactinemia. Drug interactions: additive sedation with CNS depressants; additive extrapyramidal effects with typical antipsychotics; reduced absorption of digoxin (slower gastric emptying); increased absorption of acetaminophen, cyclosporine; concurrent MAOI use can precipitate hypertensive crisis. Half-life 5 to 6 hours, prolonged in renal impairment - reduce dose. Pregnancy Category B (commonly used for hyperemesis gravidarum). Passes into breast milk. Elderly are at high risk for tardive dyskinesia and extrapyramidal symptoms; avoid if possible. Monitor for movement disorders, blood pressure, and renal function. Limit total duration of therapy to 12 weeks.
Adult Dosing
Pediatric Dosing
0.1 to 0.2 mg/kg IV/IM/PO every 6 to 8 hours. Use with caution due to higher extrapyramidal symptom risk in children. Not commonly used in tactical EMS pediatric care.
Pharmacokinetics
Peak Effect: IV: 15 minutes. PO: 1 to 2 hours.
Duration: 1 to 2 hours.
Storage and Handling
Store at room temperature. Protect from light. Injectable formulation is stable in standard EMS storage conditions.
Reconstitution:
Injectable available as 5 mg/mL solution. Can be diluted in 50 mL of compatible IV fluid (normal saline, D5W, or LR) and infused over 15 minutes to reduce akathisia risk. Compatible with most standard IV solutions; check for specific drug compatibility before co-infusion.
TCCC and TECC Role
Metoclopramide is not in the TCCC core formulary; ondansetron is the TCCC standard antiemetic. Metoclopramide appears in tactical EMS supplemental formularies primarily for migraine nausea and gastroparesis-related vomiting that does not respond to 5-HT3 antagonists. In TECC settings, ondansetron remains first-line. Metoclopramide carries enough operational risk (sedation, dystonia, akathisia) that it is classified as non-mission-capable on most TEMS formularies - the operator is off duty after a dose.
Metoclopramide's prokinetic property and dual antiemetic mechanism make it useful where ondansetron has failed or where delayed gastric emptying is the underlying problem (gastroparesis, diabetic patient with nausea). For routine post-trauma or post-opioid nausea, ondansetron is the better operational choice. Migraine-associated nausea in a non-operational patient is a reasonable indication where metoclopramide adds value over ondansetron alone, particularly when given IM.
Confusing akathisia for worsening clinical condition. Patients given metoclopramide can develop intense restlessness and inability to sit still within 30 to 60 minutes, often mistaken for anxiety, worsening pain, or psychiatric decompensation. The correct treatment is diphenhydramine 25 to 50 mg IV/IM and stopping metoclopramide. The other mistake is rapid IV push, which causes the same akathisia syndrome - administer over at least 1 to 2 minutes, ideally diluted and given over 15 minutes.
This drug profile is provided as educational reference material for trained medical providers. It is not medical advice, not a substitute for formal training, and not a substitute for current published guidelines or medical direction.
Drug administration is governed by your scope of practice, agency standing orders, medical director protocols, and applicable state and federal regulations. Controlled substances are subject to additional handling, accountability, and documentation requirements per DEA and state law. Always verify dosing, indications, contraindications, and route of administration against current published guidelines and your local protocols before administration.
If this content is being viewed during a medical emergency, call 911 immediately and follow the direction of your local emergency dispatch and medical control. Do not use this reference as a substitute for emergency medical services.
Drug information evolves. Last reviewed dates and source citations are provided for each entry. Confirm currency against the cited source before clinical use.
Penn Tactical Solutions publishes this reference for educational purposes. PTS does not provide medical direction and does not assume responsibility for clinical decisions made in the field. Clinical responsibility rests with the administering provider, their medical director, and their agency.
Educational reference for trained medical providers. Not medical advice. Not a substitute for formal training, current published guidelines, or medical direction. Drug administration is governed by your scope of practice, agency standing orders, medical director protocols, and applicable state and federal regulations. Controlled substances require additional storage, accountability, and documentation per DEA and state law.
In a medical emergency, call 911. This reference is not a substitute for emergency medical services.
Verify dosing, indications, and contraindications against current published guidelines and your local protocols before administration. Confirm content currency against the source citation. Penn Tactical Solutions does not provide medical direction. Clinical responsibility rests with the administering provider, their medical director, and their agency.
Metoclopramide
| IV/IO | 10 mg IV over 1 to 2 minutes (rapid administration causes restlessness and akathisia). For chemotherapy nausea: 1 to 2 mg/kg IV 30 minutes before chemotherapy, then every 2 to 3 hours. (1 to 3 minutes) |
| IM | 10 mg IM. Useful when IV access is not available, particularly in migraine treatment. (10 to 15 minutes) |
| IN | None (None) |
| PO | 10 mg PO 30 minutes before meals and at bedtime (gastroparesis). 10 to 15 mg PO 30 minutes before meals and at bedtime (GERD). (30 to 60 minutes) |