should not be used to treat hypotension associated with promethazine hydrochloride tablets overdose. anticholinergics - concomitant use of other agents with anticholinergic properties should be undertaken with caution. monoamine oxidase inhibitors (maoi) - drug interactions, including an increased incidence of extrapyramidal effects, have been reported when some maoi and phenothiazines are used concomitantly. this possibility should be considered with promethazine hydrochloride tablets.

ehicle or operating machinery. the impairment may be amplified by concomitant use of other central-nervous-system depressants such as alcohol, sedatives/hypnotics (including barbiturates), narcotics, narcotic analgesics, general anesthetics, tricyclic antidepressants, and tranquilizers; therefore such agents should either be eliminated or given in reduced dosage in the presence of promethazine hcl (see precautions-information for patients and drug interactions ). respiratory depression promethazine hydrochloride tablets may lead to potentially fatal respiratory depression. use of promethazine hydrochloride tablets in patients with compromised respiratory function (e.g., copd, sleep apnea) should be avoided. lower seizure threshold promethazine hydrochloride tablets may lower seizure threshold. they should be used with caution in persons with seizure disorders or in persons who are using concomitant medications, such as narcotics or local anesthetics, which may also affect seizure threshold. bone-marrow depression promethazine hydrochloride tablets should be used with caution in patients with bone-marrow depression. leukopenia and agranulocytosis have been reported, usually when promethazine hcl has been used in association with other known marrow-toxic agents. neuroleptic malignant syndrome a potentially fatal symptom complex sometimes referred to as neuroleptic malignant syndrome (nms) has been reported in association with promethazine hcl alone or in combination with antipsychotic drugs. clinical manifestations of nms are hyperpyrexia, muscle rigidity, altered mental status and evidence of autonomic instability (irregular pulse or blood pressure, tachycardia, diaphoresis and cardiac dysrhythmias). 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, drug fever and primary central nervous system (cns) pathology. the management of nms should include 1) immediate discontinuation of promethazine hcl, antipsychotic drugs, if any, 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. there is no general agreement about specific pharmacological treatment regimens for uncomplicated nms. since recurrences of nms have been reported with phenothiazines, the reintroduction of promethazine hcl should be carefully considered. use in pediatric patients promethazine hydrochloride tablets usp are contraindicated for use in pediatric patients less than two years of age. caution should be exercised when administering promethazine hydrochloride tablets to pediatric patients 2 years of age and older because of the potential for fatal respiratory depression. respiratory depression and apnea, sometimes associated with death, are strongly associated with promethazine products and are not directly related to individualized weight-based dosing, which might otherwise permit safe administration. concomitant administration of promethazine products with other respiratory depressants has an association with respiratory depression, and sometimes death, in pediatric patients. antiemetics are not recommended for treatment of uncomplicated vomiting in pediatric patients, and their use should be limited to prolonged vomiting of known etiology. the extrapyramidal symptoms which can occur secondary to promethazine hydrochloride tablets administration may be confused with the cns signs of undiagnosed primary disease, e.g., encephalopathy or reye’s syndrome. the use of promethazine hcl tablets should be avoided in pediatric patients whose signs and symptoms may suggest reye’s syndrome or other hepatic diseases. excessively large dosages of antihistamines, including promethazine hydrochloride tablets, in pediatric patients may cause sudden death (see overdosage ). hallucinations and convulsions have occurred with therapeutic doses and overdoses of promethazine in pediatric patients. in pediatric patients who are acutely ill associated with dehydration, there is an increased susceptibility to dystonias with the use of promethazine hcl. other considerations administration of promethazine hcl has been associated with reported cholestatic jaundice.

ine hydrochloride tablets, syrup, or rectal suppositories, 12.5 to 25 mg twice daily, may be administered. nausea and vomiting antiemetics should not be used in vomiting of unknown etiology in children and adolescents (see warnings-use in pediatric patients ). the average effective dose of promethazine hydrochloride for the active therapy of nausea and vomiting in children or adults is 25 mg. when oral medication cannot be tolerated, the dose should be given parenterally (cf. promethazine injection) or by rectal suppository. 12.5- to 25-mg doses may be repeated, as necessary, at 4- to 6-hour intervals. for nausea and vomiting in children, the usual dose is 0.5 mg per pound of body weight, and the dose should be adjusted to the age and weight of the patient and the severity of the condition being treated. for prophylaxis of nausea and vomiting, as during surgery and the postoperative period, the average dose is 25 mg repeated at 4- to 6-hour intervals, as necessary. sedation this product relieves apprehension and induces a quiet sleep from which the patient can be easily aroused. administration of 12.5 to 25 mg promethazine hydrochloride by the oral route or by rectal suppository at bedtime will provide sedation in children. adults usually require 25 to 50 mg for nighttime, presurgical, or obstetrical sedation. pre- and postoperative use promethazine hydrochloride in 12.5- to 25-mg doses for children and 50-mg doses for adults the night before surgery relieves apprehension and produces a quiet sleep. for preoperative medication, children require doses of 0.5 mg per pound of body weight in combination with an appropriately reduced dose of narcotic or barbiturate and the appropriate dose of an atropine-like drug. usual adult dosage is 50 mg promethazine hcl with an appropriately reduced dose of narcotic or barbiturate and the required amount of a belladonna alkaloid. postoperative sedation and adjunctive use with analgesics may be obtained by the administration of 12.5 to 25 mg in children and 25- to 50-mg doses in adults. promethazine hydrochloride tablets are contraindicated for children under 2 years of age.

also been reported. (see warnings-neuroleptic malignant syndrome .) paradoxical reactions hyperexcitability and abnormal movements have been reported in patients following a single administration of promethazine hcl. consideration should be given to the discontinuation of promethazine hcl and to the use of other drugs if these reactions occur. respiratory depression, nightmares, delirium, and agitated behavior have also been reported in some of these patients.

should not be used to treat hypotension associated with promethazine hydrochloride tablets overdose. anticholinergics - concomitant use of other agents with anticholinergic properties should be undertaken with caution. monoamine oxidase inhibitors (maoi) - drug interactions, including an increased incidence of extrapyramidal effects, have been reported when some maoi and phenothiazines are used concomitantly. this possibility should be considered with promethazine hydrochloride tablets.

regnancy only if the potential benefit justifies the potential risk to the fetus. nonteratogenic effects promethazine hydrochloride tablets administered to a pregnant woman within two weeks of delivery may inhibit platelet aggregation in the newborn.