DrugindexOnline^{2nd edition}

Pronouncation: (proe-METH-a-zeen HYE-droe-KLOR-ide/DEX-troe-meth-OR-fan HYE-droe-BROE-mide)
Class: Upper respiratory combination

Trade Names:
Promethazine with Dextromethorphan
- Syrup 6.25 mg promethazine hydrochloride/15 mg dextromethorphan hydrobromide per 5 mL

Indications and Usage

Temporary relief of coughs and upper respiratory tract symptoms associated with allergy or the common cold.

Contraindications

Lower respiratory tract symptoms (including asthma); patients receiving MAOIs; children younger than 2 yr of age; hypersensitivity or idiosyncratic reaction to phenothiazines or any component of the product.

Dosage and Administration

Adults

PO 1 tsp (5 mL) every 4 to 6 h (max, 30 mL per 24 h).

Children 6 to younger than 12 yr of age

PO 0.5 to 1 tsp (2.5 to 5 mL) every 4 to 6 h (max, 20 mL per 24 h).

Children 2 to younger than 6 yr of age

PO 0.25 to 0.5 tsp (1.25 to 2.5 mL) every 4 to 6 h (max, 10 mL per 24 h).

Storage/Stability

Store at 59° to 77°F. Protect from light. Dispense in a tightly closed, light-resistant container.

Drug Interactions

Anticholinergics

May decrease action of promethazine.

Barbiturate anesthetics

Coadministration with promethazine may increase the risk of neuromuscular excitation and hypotension.

CNS depressants (eg, alcohol, hypnotics, narcotic analgesics, sedatives, tranquilizers, tricyclic antidepressants)

Effects are additive. Avoid coadministration of these agents or give in reduced dosages to patients receiving promethazine.

Epinephrine

Because promethazine may reverse the vasopressor effect of epinephrine, do not use epinephrine to treat promethazine-associated overdose.

MAOIs

Coadministration with promethazine/dextromethorphan is contraindicated. Hyperpyrexia, hypotension, and death have been reported.

Coadministration with promethazine may prolong and intensify anticholinergic effects; may cause hypotension and extrapyramidal effects.

Laboratory Test Interactions

Pregnancy tests based on immunological reactions between human chorionic sonadotropin (hCG) and anti-hCG result in false-negative or false-positive interpretations; glucose tolerance tests may produce an increase in blood glucose.

Adverse Reactions

Cardiovascular

Hypertension, hypotension.

CNS

Confusion, disorientation, dizziness, drowsiness, extrapyramidal symptoms, sedation, sleepiness.

Dermatologic

Photosensitivity.

EENT

Blurred vision.

GI

Dry mouth, GI disturbances, nausea, vomiting.

Hematologic-Lymphatic

Agranulocytosis, leukopenia, thrombocytopenia.

Precautions

Warnings Do not use in patients younger than 2 yr of age because of potential for fatal respiratory depression. Administer with caution to children older than 2 yr of age.

Pregnancy

Category C .

Lactation

Undetermined.

Children

Contraindicated for use in children younger than 2 yr of age.

Special Risk Patients

Use with caution in atopic children, debilitated patients, and patients with narrow-angle glaucoma, stenosing peptic ulcer, pyloroduodenal obstruction, liver function impairment, and urinary bladder obstruction caused by symptomatic prostatic hypertrophy, bone marrow depression, and narrowing of the bladder neck.

Sleep apnea

Avoid administering to patients with a history of sleep apnea.

Seizure threshold

Drug may lower seizure threshold. Use with caution in patients with known seizure disorders, or when giving in combination with narcotics or local anesthetics that may alter seizure threshold.

Overdosage

Symptoms

Promethazine

Dry mouth; fixed pupils; flushing; GI symptoms; mild depression of the CNS and CV systems; paradoxical hyperexcitability and nightmares in children; profound hypotension; respiratory depression; seizures; stimulation may be evident, especially in children and elderly patients; unconsciousness.

Dextromethorphan

Central excitement, mental confusion, respiratory depression, and toxic psychosis, including hyperactivity and marked visual and auditory hallucinations.

Patient Information

• Instruct patient on how to store, administer, and dispose of outdated medication.
• Advise patient that drug may cause drowsiness or impaired judgment or thinking, and to use caution while driving, riding a bike, or performing other tasks requiring mental alertness until tolerance is determined.
• Caution patient that medication may cause sensitivity to sunlight and to avoid unnecessary exposure to ultraviolet (UV) light (eg, sunlight, tanning booths) and to use sunscreen and wear protective clothing when exposed to UV light until tolerance is determined.
• Instruct patient to take exactly as prescribed and not to change the dose or discontinue therapy unless advised by health care provider.
• Advise patient to report any involuntary muscle movements.