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Reglan Side Effects

Generic Name: metoclopramide

Note: This page contains side effects data for the generic drug metoclopramide. It is possible that some of the dosage forms included below may not apply to the brand name Reglan.

For the Consumer

Applies to metoclopramide: oral solution, oral syrup, oral tablet, oral tablet disintegrating

Other dosage forms:

As well as its needed effects, metoclopramide (the active ingredient contained in Reglan) may cause unwanted side effects that require medical attention.

Severity: Major

If any of the following side effects occur while taking metoclopramide, check with your doctor immediately:

  • Abdominal or stomach pain or tenderness
  • chills
  • clay colored stools
  • convulsions (seizures)
  • dark urine
  • difficulty with breathing
  • difficulty with speaking or swallowing
  • dizziness or fainting
  • fast or irregular heartbeat
  • fever
  • general feeling of tiredness or weakness
  • headache (severe or continuing)
  • inability to move the eyes
  • increase in blood pressure
  • increased sweating
  • itching
  • lip smacking or puckering
  • loss of appetite
  • loss of balance control
  • loss of bladder control
  • mask-like face
  • muscle spasms of the face, neck, and back
  • nausea and vomiting
  • puffing of the cheeks
  • rapid or worm-like movements of the tongue
  • shuffling walk
  • skin rash
  • sore throat
  • stiffness of the arms or legs
  • swelling of the feet or lower legs
  • tic-like or twitching movements
  • trembling and shaking of the hands and fingers
  • twisting movements of the body
  • uncontrolled chewing movements
  • uncontrolled movements of the arms and legs
  • unusually pale skin
  • weakness of the arms and legs
  • yellow eyes or skin

If any of the following symptoms of overdose occur while taking metoclopramide, get emergency help immediately:

Symptoms of overdose:
  • Confusion
  • drowsiness (severe)

Severity: Minor

Some metoclopramide side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

More common:
  • Diarrhea
  • drowsiness
  • restlessness
Less common or rare:
  • Breast tenderness and swelling
  • changes in menstruation
  • constipation
  • decreased interest in sexual intercourse
  • inability to have or keep an erection
  • increased flow of breast milk
  • increased need to urinate
  • loss in sexual ability, desire, drive, or performance
  • mental depression
  • passing urine more often
  • skin rash
  • trouble sleeping
  • unusual dryness of the mouth
  • unusual irritability

For Healthcare Professionals

Applies to metoclopramide: compounding powder, injectable solution, oral concentrate, oral syrup, oral tablet, oral tablet disintegrating

Nervous system

Tardive dyskinesia involves involuntary, dyskinetic, repetitive movements and may be more common in elderly women. Tardive dyskinesia may be irreversible and is related to both the duration of therapy and the total amount of drug consumed. Frequent discontinuation and resumption of therapy may predispose patients to the development of tardive dyskinesia.

Dystonias frequently involve tongue protrusions, muscle rigidity, torticollis, and opisthotonos. Dystonias usually resolve after metoclopramide (the active ingredient contained in Reglan) discontinuation, but may require antihistamine and antiparkinsonian therapy if symptoms are severe or if respiration is compromised. Treatment of dystonic reactions and extrapyramidal effects, in addition to general supportive measures, may include judicious use of one or more of the following: benztropine or diphenhydramine.

Hyperthermia, altered consciousness, autonomic dysfunction, and muscle rigidity are the hallmarks of the neuroleptic malignant syndrome. The neuroleptic malignant syndrome is associated with a case fatality rate of about 20%. Immediate discontinuation of metoclopramide therapy, consideration of dantrolene administration, as well as intensive monitoring and supportive care are indicated.

Drug-induced parkinsonian symptoms due to metoclopramide may be misdiagnosed and inappropriately treated with dopaminergic agents. Parkinsonian-like symptoms have occurred, more commonly within the first 6 months from the start of therapy with metoclopramide, but occasionally after longer periods. Caution should be exercised when diagnosing movement disorders in patients currently being treated with metoclopramide. Additionally, metoclopramide should be avoided in patients with confirmed Parkinson's disease.

Patients with AIDS or HIV-positive may be at an increased risk of developing acute dystonia to metoclopramide use. Decreases in dopamine levels have been observed in a study of AIDS patients without clinical neurologic disease. Similarly, HIV-positive patients have shown a decreased response in serum prolactin during intravenous infusion of metoclopramide when compared with controls, interpreted as an indirect evidence of a diminished endogenous dopamine tone.[Ref]

Very common (10% or more): Drowsiness Up to 70%), fatigue, restlessness, lassitude
Uncommon (0.1% to 1%): Confusion, agitation, anxiety
Rare (0.01% to 0.1%): Seizures, hallucinations
Very rare (less than 0.01%): Neuroleptic malignant syndrome
Frequency not reported: Tardive dyskinesia, dystonia, pseudo-parkinsonism, akathisia[Ref]


Frequency not reported: Galactorrhea, amenorrhea, gynecomastia, impotence secondary to hyperprolactinemia, transient increase in circulating aldosterone levels and causing edema[Ref]


Frequency not reported: Depression, anxiety, mania, psychosis, insomnia[Ref]

Depression may occur in patients without prior history of depression or other psychiatric illness and may be severe. Suicidal ideation may be present. Several reports suggest that dose reduction may alleviate depressive symptomatology. In addition, reintroduction of metoclopramide with slow titration of the dose upwards to a therapeutic level has been successful in some patients.[Ref]


Very rare (less than 0.01%): Abnormalities of cardiac conduction (e.g., bradycardia, asystole, heart block, sinus arrest, cardiac arrest)
Frequency not reported: Hypotension, hypertension, supraventricular tachycardia, bradycardia, fluid retention, acute congestive heart failure, atrioventricular (AV) block, hypertensive crisis in patients with pheochromocytoma, transient flushing of the face and upper body (without alterations in vital signs, following high doses IV)[Ref]

It is postulated that metoclopramide may indirectly cause release of catecholamines from tumors in pheochromocytoma patients. Hypertensive crisis may ensue. The use of metoclopramide is considered contraindicated in patients with pheochromocytoma.

Hypertensive crisis has been documented in the absence of pheochromocytoma as well. The manufacturer recommends cautious use of metoclopramide in patients with essential hypertension.

Sinus bradycardia (50 beats per minute) progressing to complete heart block with sinus arrest has been reported in a 54-year-old man after receiving metoclopramide 10 mg IV. Asystole lasted approximately 25 seconds, followed by a spontaneous increase in heart rate to 80 beats per minute in sinus rhythm with a blood pressure of 140/70 mm Hg. Similar effects were observed on rechallenge with a dose of metoclopramide 5 mg given slowly. No changes in ST segment or QRS complexes were observed on electrocardiogram.[Ref]


Patients with NADH-cytochrome b5 reductase deficiency who need to receive metoclopramide (the active ingredient contained in Reglan) are at increased risk of developing methemoglobinemia and/or sulfhemoglobinemia. The treatment of metoclopramide-induced methemoglobinemia with methylene blue is not recommended in patients with G6PD deficiency.[Ref]

Rare (0.01% to 0.1%): Leucopenia, neutropenia, porphyria, agranulocytosis
Very rare (less than 0.01%): Red cell disorders (such as methemoglobinemia) (which could be related to NADH cytochrome b5 reductase deficiency particularly in neonates), sulfhemoglobinemia (particularly at high doses)[Ref]


Rare (0.01% to 0.1%): Hepatotoxicity (jaundice, altered liver function tests, when this drug was administered with other drugs with known hepatotoxic potential)
Very rare (less than 0.01%): Arteriovenous shunting and cholestasis in conjunction with hepatic hemangiomatosis
Frequency not reported: Porphyria[Ref]


Frequency not reported: Nausea, bowel disturbances (primarily diarrhea)[Ref]


Frequency not reported: Rash, urticaria, bronchospasm (especially in patients with a history of asthma), anaphylaxis, angioneurotic edema, glossal or laryngoedema reaction[Ref]


Frequency not reported: Nausea, bowel disturbances (primarily diarrhea)[Ref]


Frequency not reported: Bronchospasm[Ref]


Frequency not reported: Visual disturbances, decrease in pupil diameter, transiently depressed reflex dilation[Ref]


Very rare (less than 0.01%): Dystonic reaction[Ref]


The incidence of side effects correlates with dose and duration of therapy. The elderly may be more susceptible to developing adverse effects due to the changes in organ function, concomitant diseases, and other drug therapies.[Ref]


Very rare (less than 0.01%): Hypersensitivity (Including anaphylactic/anaphylactoid reactions, including symptoms such as tongue swelling/edema)[Ref]


1. "Product Information. Reglan (metoclopramide)." Wyeth-Ayerst Laboratories, Philadelphia, PA.

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. Cerner Multum, Inc. "Australian Product Information." O 0

It is possible that some side effects of Reglan may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.