Promethazine precautions

List of precautions
General Drug/lab test interactions Carcinogenesis Mutagenesis Impairment of fertility Pregnancy Labor & delivery Nursing mothers Pediatric use Geriatric use
 * Teratogenic effects
 * Nonteratogenic effects

General
Drugs having anticholinergic properties should be used with caution in patients with narrow-angle glaucoma, prostatic hypertrophy, stenosing peptic ulcer, pyloroduodenal obstruction, and bladder-neck obstruction. Promethazine HCl Syrup Plain should be used cautiously in persons with cardiovascular disease or with impairment of liver function. Return to top

Drug/lab test interactions
The following laboratory tests may be affected in patients who are receiving therapy with Promethazine HCl: Return to top
 * Pregnancy Tests
 * Diagnostic pregnancy tests based on immunological reactions between HCG and anti-HCG may result in false-negative or false-positive interpretations.
 * Glucose Tolerance Test
 * An increase in blood glucose has been reported in patients receiving Promethazine HCl.

Carcinogenesis
Long-term animal studies have not been performed to assess the carcinogenic potential of Promethazine, nor are there other animal or human data concerning carginogenicity with this drug. Return to top

Mutagenesis
There is no animal or human data concerning mutagenicity with this drug. Promethazine was nonmutagenic in the Salmonella test system of Ames. Return to top

Impairment of fertility
There is no animal or human data concerning impairment of fertility with this drug.Return to top

Pregnancy

 * Pregnancy category C. Return to top

Teratogenic effects
Teratogenic effects have not been demonstrated in rat-feeding studies at doses of 6.25 and 12.5 mg/kg of Promethazine HCl. These doses are from approximately 2.1 to 4.2 times the maximum recommended total daily dose of Promethazine for a 50-kg subject, depending upon the indication for which the drug is prescribed. Daily doses of 25 mg/kg intraperitoneally have been found to produce fetal mortality in rats. Specific studies to test the action of the drug on parturition, lactation, and development of the animal neonate were not done, but a general preliminary study in rats indicated no effect on these parameters. Although antihistamines have been found to produce fetal mortality in rodents, the pharmacological effects of histamine in the rodent do not parallel those in man. There are no adequate and well-controlled studies of Promethazine HCl Syrup Plain in pregnant women. Promethazine HCl Syrup Plain should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Return to top

Nonteratogenic effects
Promethazine HCl Syrup Plain administered to a pregnant woman within two weeks of delivery may inhibit platelet aggregation in the newborn. Return to top

Labor & delivery
Promethazine HCl Syrup Plain may be used alone or as an adjunct to narcotic analgesics during labor. Limited data suggest that use of Promethazine HCl Syrup Plain during labor and delivery does not have an appreciable effect on the duration of labor or delivery and does not increase the risk of need for intervention in the newborn. The effect on later growth and development of the newborn is unknown. Return to top

Nursing mothers
It is not known whether Promethazine HCl is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from Promethazine HCl Syrup Plain, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. Return to top

Pediatric use
Promethazine HCl Syrup Plain is contraindicated for use in pediatric patients less than two years of age. Promethazine HCl Syrup Plain should be used with caution in pediatric patients 2 years of age and older.Return to top

Geriatric use
Clinical studies of Promethazine formulations did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy. Sedating drugs may cause confusion and over-sedation in the elderly; elderly patients generally should be started on low doses of Promethazine HCl Syrup Plain and observed closely. Return to top