Respiratory Depression in Children and Death Related to Ultra-Rapid Metabolism of Codeine to Morphine
Respiratory Depression in Children
The combination of promethazine hydrochloride and codeine phosphate is contraindicated in pediatric patients less than 6 years of age. Concomitant administration of promethazine products with other respiratory depressants has an association with respiratory depression, and sometimes death, in pediatric patients.
Postmarketing cases of respiratory depression, including fatalities, have been reported with use of promethazine hydrochloride in pediatric patients less than 2 years of age. A wide range of weight-based doses of promethazine hydrochloride have resulted in respiratory depression in these patients.
Death Related to Ultra-Rapid Metabolism of Codeine to Morphine
Respiratory depression and death have occurred in children who received codeine following tonsillectomy and/or adenoidectomy and had evidence of being ultra-rapid metabolizers of codeine due to a CYP2D6 polymorphism.
Each 5 mL (one teaspoonful), for oral administration contains: Promethazine hydrochloride 6.25 mg; codeine phosphate 10 mg in a flavored syrup base with a pH between 4.8 and 5.4. Alcohol 7%.
Inactive ingredients: Artificial and natural flavors, citric acid, D&C Red 33, FD&C Blue 1, FD&C Yellow 6, glycerin, saccharin sodium, sodium benzoate, sodium citrate, sodium propionate, water, and other ingredients.
Codeine is one of the naturally occurring phenanthrene alkaloids of opium derived from the opium poppy, it is classified pharmacologically as a narcotic analgesic. Codeine phosphate may be chemically designated as 7,8-Didehydro-4, 5α-epoxy-3-methoxy-17-methylmorphinan-6-α-ol phosphate (1:1)(salt)hemihydrate.
The phosphate salt of codeine occurs as white, needle-shaped crystals or white crystalline powder. Codeine phosphate is freely soluble in water and slightly soluble in alcohol. It has a molecular weight of 406.37, a molecular formula of C18H21NO3•H3PO4 • ½ H2O, and the following structural formula:
Promethazine hydrochloride, a phenothiazine derivative, is chemically designated as (±)-10-[2(Dimethylamino)propyl] phenothiazine monohydrochloride.
Promethazine hydrochloride occurs as a white to faint yellow, practically odorless, crystalline powder which slowly oxidizes and turns blue on prolonged exposure to air. It is freely soluble in water and soluble in alcohol. It is soluble in water and freely soluble in alcohol. It has a molecular weight of 320.88, a molecular formula of C17H20N2S•HCl, and the following structural formula:
Promethazine HCl and Codeine Phosphate Oral Solution is indicated for the temporary relief of coughs and upper respiratory symptoms associated with allergy or the common cold.
DOSAGE AND ADMINISTRATION
It is important that Promethazine HCl and Codeine Phosphate Oral Solution is measured with an accurate measuring device (see PATIENT INFORMATION). A household teaspoon is not an accurate measuring device and could lead to overdosage, especially when half a teaspoon is to be measured. It is strongly recommended that an accurate measuring device be used. A pharmacist can provide an appropriate device and can provide instructions for measuring the correct dose.