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.

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.

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.

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)

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.

Nervous system side effects have been commonly reported and included drowsiness, fatigue, restlessness, and lassitude in approximately 10% of patients. Drowsiness may occur in up to 70% of cancer patients treated with high-dose (1 to 2 mg/kg/dose) metoclopramide. Tardive dyskinesia, dystonia, pseudo-parkinsonism, and the neuroleptic malignant syndrome have also been reported. In addition, cases of akathisia have been reported. Seizures and hallucinations have been reported rarely. At least one case of lightheadedness has also been reported.


Endocrine side effects have included galactorrhea, amenorrhea, gynecomastia, and impotence secondary to hyperprolactinemia. In addition, metoclopramide (the active ingredient contained in Reglan) may cause a transient increase in circulating aldosterone levels and subsequently cause edema.


Psychiatric side effects have included depression, anxiety, mania, psychosis, and insomnia.

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.


Cardiovascular side effects have included hypertension, hypotension, supraventricular tachycardia, bradycardia, and cardiac arrest. In addition, metoclopramide (the active ingredient contained in Reglan) is associated with hypertensive crisis in patients with pheochromocytoma and has been implicated in a case of congestive heart failure.

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.


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.

Hematologic side effects including leukopenia, neutropenia, porphyria, and agranulocytosis have been reported rarely. Methemoglobinemia has also been reported with metoclopramide use in adults, but may be more common in infants who are treated with high doses.


Hepatic side effects have included rare reports of elevations in liver function tests and jaundice. A case of arteriovenous shunting and cholestasis in conjunction with hepatic hemangiomatosis has been reported.

A 22-year-old female, treated with metoclopramide 10 to 15 mg per day for 7 to 8 months for abdominal pain, developed hepatic hemangiomatosis with arteriovenous shunting and cholestasis. Hyperprolactinemia, galactorrhea, amenorrhea, and virilization were also noted on initial presentation. The patient was placed on a waiting list for liver transplantation. However, complete, albeit slow, resolution occurred following discontinuation of metoclopramide.


Genitourinary side effects have included urinary frequency, incontinence, and urinary retention.


Hypersensitivity side effects have included rash, urticaria, bronchospasm, angioneurotic edema, and glossal or laryngoedemal reactions.


Gastrointestinal side effects have included nausea and diarrhea.


Respiratory side effects have been reported rarely. A case of metoclopramide-induced bronchospasm is reported in the literature.


Other side effects have included porphyria, local pain during intravenous injection, and transient flushing during high-dose infusion. At least one case of generalized weakness has been reported.


Renal side effects have included urinary frequency and incontinence.


Ocular side effects have included visual disturbances. Decrease in pupil diameter and transiently depressed reflex dilation have been reported in patients undergoing lower abdominal surgery under combined epidural/general anesthesia.


Musculoskeletal side effects have included a case of dystonic reaction.

A 28-year-old female experienced dystonic reaction coincident with metoclopramide therapy. She had started taking metoclopramide the day before her presentation to the hospital. Her symptoms resolved six to eight hours after onset.


In general, the incidence of side effects correlates with dose and duration of metoclopramide (the active ingredient contained in Reglan) therapy. The elderly may be more susceptible to developing adverse effects due to the changes in organ function, concomitant diseases, and other drug therapies.

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.