METOCLOPRAMIDE 5 mg/mL Injection, Solution — NDC 51662-1670-3 (Billing 51662-1670-03)

Neuroleptic Malignant Syndrome (NMS) There have been rare reports of an uncommon but potentially fatal symptom complex sometimes referred to as Neuroleptic Malignant Syndrome (NMS) associated with metoclopramide. Clinical manifestations of NMS include hyperthermia, muscle rigidity, altered consciousness, and evidence of autonomic instability (irregular pulse or blood pressure, tachycardia, diaphoresis and cardiac arrhythmias). The diagnostic evaluation of patients with this syndrome is complicated.

In arriving at a diagnosis, it is important to identify cases where the clinical presentation includes both serious medical illness (e.g., pneumonia, systemic infection, etc.) and untreated or inadequately treated extrapyramidal signs and symptoms (EPS). Other important considerations in the differential diagnosis include central anticholinergic toxicity, heat stroke, malignant hyperthermia, drug fever and primary central nervous system (CNS) pathology. The management of NMS should include 1) immediate discontinuation of metoclopramide and other drugs not essential to concurrent therapy, 2) intensive symptomatic treatment and medical monitoring, and 3) treatment of any concomitant serious medical problems for which specific treatments are available.

Bromocriptine and dantrolene sodium have been used in treatment of NMS, but their effectiveness have not been established (see ADVERSE REACTIONS). Extrapyramidal Symptoms (EPS) Acute Dystonic Reactions Acute dystonic reactions occur in approximately 1 in 500 patients treated with the usual adult dosages of 30 to 40 mg/day of metoclopramide. These usually are seen during the first 24 to 48 hours of treatment with metoclopramide, occur more frequently in pediatric patients and adult patients less than 30 years of age and are even more frequent at the higher doses used in prophylaxis of vomiting due to cancer chemotherapy.

These symptoms may include involuntary movements of limbs and facial grimacing, torticollis, oculogyric crisis, rhythmic protrusion of tongue, bulbar type of speech, trismus, or dystonic reactions resembling tetanus. Rarely, dystonic reactions may present as stridor and dyspnea, possibly due to laryngospasm. If these symptoms should occur, inject 50 mg Benadryl® (diphenhydramine hydrochloride) intramuscularly, and they usually will subside.

Cogentin® (benztropine mesylate), 1 to 2 mg intramuscularly, may also be used to reverse these reactions. Tardive Dyskinesia (see Boxed Warnings) Treatment with metoclopramide can cause tardive dyskinesia (TD), a potentially irreversible and disfiguring disorder characterized by involuntary movements of the face, tongue, or extremities. The risk of tardive dyskinesia increases with the duration of treatment and the total cumulative dose.

An analysis of utilization patterns showed that about 20% of patients who used metoclopramide took it longer than 12 weeks. Treatment with metoclopramide for longer than the recommended 12 weeks should be avoided in all but rare cases where therapeutic benefit is thought to outweigh the risk of developing TD. Although the risk of developing TD in the general population may be increased among the elderly, women, and diabetics, it is not possible to predict which patients will develop metoclopramide-induced TD.

Both the risk of developing TD and the likelihood that TD will become irreversible increase with duration of treatment and total cumulative dose. Metoclopramide should be discontinued in patients who develop signs or symptoms of TD. There is no known effective treatment for established cases of TD, although in some patients, TD may remit, partially or completely, within several weeks to months after metoclopramide is withdrawn.

Metoclopramide itself may suppress, or partially suppress, the signs of TD, thereby masking the underlying disease process. The effect of this symptomatic suppression upon the long-term course of TD is unknown. Therefore, metoclopramide should not be used for the symptomati… [Excerpted — this section continues on DailyMed.]

In general, the incidence of adverse reactions correlates with the dose and duration of metoclopramide administration. The following reactions have been reported, although in most instances, data do not permit an estimate of frequency. CNS Effects Restlessness, drowsiness, fatigue and lassitude may occur in patients receiving the recommended prescribed dosage of metoclopramide injection.

Insomnia, headache, confusion, dizziness, or mental depression with suicidal ideation also may occur (see WARNINGS). In cancer chemotherapy patients being treated with 1 to 2 mg/kg per dose, incidence of drowsiness is about 70%. There are isolated reports of convulsive seizures without a clear-cut relationship to metoclopramide.

Rarely, hallucinations have been reported. Extrapyramidal Reactions (EPS) Acute dystonic reactions, the most common type of EPS associated with metoclopramide, occur in approximately 0.2% of patients (1 in 500) treated with 30 to 40 mg of metoclopramide per day. In cancer chemotherapy patients receiving 1 to 2 mg/kg per dose, the incidence is 2% in patients over the ages of 30 to 35, and 25% or higher in pediatric patients and adult patients less than 30 years of age who have not had prophylactic administration of diphenhydramine.

Symptoms include involuntary movements of limbs, facial grimacing, torticollis, oculogyric crisis, rhythmic protrusion of tongue, bulbar type of speech, trismus, opisthotonus (tetanus-like reactions) and rarely, stridor and dyspnea, possibly due to laryngospasm; ordinarily these symptoms are readily reversed by diphenhydramine (see WARNINGS). Parkinsonian-like symptoms may include bradykinesia, tremor, cogwheel rigidity, mask-like facies (see WARNINGS). Tardive dyskinesia most frequently is characterized by involuntary movements of the tongue, face, mouth or jaw, and sometimes by involuntary movements of the trunk and/or extremities; movements may be choreoathetotic in appearance (see WARNINGS).

Motor restlessness (akathisia) may consist of feelings of anxiety, agitation, jitteriness, and insomnia, as well as inability to sit still, pacing, and foot tapping. These symptoms may disappear spontaneously or respond to a reduction in dosage. Neuroleptic Malignant Syndrome Rare occurrences of neuroleptic malignant syndrome (NMS) have been reported.

This potentially fatal syndrome is comprised of the symptom complex of hyperthermia, muscular rigidity, altered consciousness, and autonomic instability (see WARNINGS). Endocrine Disturbances Galactorrhea, amenorrhea, gynecomastia, impotence secondary to hyperprolactinemia (see PRECAUTIONS). Fluid retention secondary to transient elevation of aldosterone (see CLINICAL PHARMACOLOGY).

Cardiovascular Hypotension, hypertension, supraventricular tachycardia, bradycardia, fluid retention, acute congestive heart failure, and possible atrioventricular (AV) block (see CONTRAINDICATIONS and PRECAUTIONS). Gastrointestinal Nausea and bowel disturbances, primarily diarrhea. Hepatic Rarely, cases of hepatotoxicity, characterized by such findings as jaundice and altered liver function tests, when metoclopramide was administered with other drugs with known hepatotoxic potential.

Renal Urinary frequency and incontinence. Hematologic A few cases of neutropenia, leukopenia, or agranulocytosis, generally without a clear-cut relationship to metoclopramide. Methemoglobinemia, in adults and especially with overdosage in neonates (see OVERDOSAGE).

Sulfhemoglobinemia in adults. Allergic Reactions A few cases of rash, urticaria, or bronchospasm, especially in patients with a history of asthma. Rarely, angioneurotic edema, including glossal or laryngeal edema.

Miscellaneous Visual disturbances, Porphyria. Transient flushing of the face and upper body, without alterations in vital signs, following high doses intravenously.

General In one study in hypertensive patients, intravenously administered metoclopramide was shown to release catecholamines, hence, caution should be exercised when metoclopramide is used in patients with hypertension. Intravenous injections of undiluted metoclopramide should be made slowly allowing 1 to 2 minutes for 10 mg since a transient but intense feeling of anxiety and restlessness, followed by drowsiness, may occur with rapid administration. Because metoclopramide produces a transient increase in plasma aldosterone, certain patients, especially those with cirrhosis or congestive heart failure, may be at risk of developing fluid retention and volume overload.

If these side effects occur at any time during metoclopramide therapy, the drug should be discontinued. Intravenous administration of Metoclopramide Injection, USP, diluted in a parenteral solution should be made slowly over a period of not less than 15 minutes. Giving a promotility drug such as metoclopramide theoretically could put increased pressure on suture lines following a gut anastomosis or closure.

This possibility should be considered and weighed when deciding whether to use metoclopramide or nasogastric suction in the prevention of postoperative nausea and vomiting. Information for Patients A patient Medication Guide is available for metoclopramide. The prescriber or health professional should instruct patients, their families, and their caregivers to read the Medication Guide and should assist them in understanding its contents.

Patients should be given the opportunity to discuss the contents of the Medication Guide and to obtain answers to any questions they may have. Refer to the accompanying Medication Guide. Metoclopramide may impair the mental and/or physical abilities required for the performance of hazardous tasks such as operating machinery or driving a motor vehicle.

The ambulatory patient should be cautioned accordingly. Drug Interactions The effects of metoclopramide on gastrointestinal motility are antagonized by anticholinergic drugs and narcotic analgesics. Additive sedative effects can occur when metoclopramide is given with alcohol, sedatives, hypnotics, narcotics or tranquilizers.

The finding that metoclopramide releases catecholamines in patients with essential hypertension suggests that it should be used cautiously, if at all, in patients receiving monoamine oxidase inhibitors. Absorption of drugs from the stomach may be diminished (e.g., digoxin) by metoclopramide, whereas the rate and/or extent of absorption of drugs from the small bowel may be increased (e.g., acetaminophen, tetracycline, levodopa, ethanol, cyclosporine). Gastroparesis (gastric stasis) may be responsible for poor diabetic control in some patients.

Exogenously administered insulin may begin to act before food has left the stomach and lead to hypoglycemia. Because the action of metoclopramide will influence the delivery of food to the intestines and thus the rate of absorption, insulin dosage or timing of dosage may require adjustment. Carcinogenesis, Mutagenesis, Impairment of Fertility A 77-week study was conducted in rats with oral doses up to about 40 times the maximum recommended human daily dose.

Metoclopramide elevates prolactin levels and the elevation persists during chronic administration. Tissue culture experiments indicate that approximately one-third of human breast cancers are prolactin-dependent in vitro, a factor of potential importance if the prescription of metoclopramide is contemplated in a patient with previously detected breast cancer. Although disturbances such as galactorrhea, amenorrhea, gynecomastia, and impotence have been reported with prolactin-elevating drugs, the clinical significance of elevated serum prolactin levels is unknown for most patients.

An increase in mammary neoplasms has been found in rodents after chronic administration of prolactin-stimulating neuroleptic drugs and metoclopramide. Neither clinical studies nor epidemiolo… [Excerpted — this section continues on DailyMed.]