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Codeine / Phenylephrine / Promethazine Dosage

Applies to the following strength(s): 10 mg-5 mg-6.25 mg/5 mL

The information at is not a substitute for medical advice. Always consult your doctor or pharmacist.

Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Cough and Nasal Congestion

5 mL orally every 4 to 6 hours as needed. Maximum dose: 30 mL/day.

Usual Pediatric Dose for Cough and Nasal Congestion

6 years to 11 years: 2.5 to 5 mL orally every 4 to 6 hours as needed. Maximum dose: 30 mL/24 hours.

12 years or older: 5 mL orally every 4 to 6 hours as needed. Maximum dose: 30 mL/24 hours.

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available


The combination of promethazine hydrochloride and codeine phosphate is contraindicated in pediatric patients less than 6 years of age, because the combination may cause fatal respiratory depression in this age population.

The FDA issued a Public Health Advisory about a very rare, but serious, side effect in nursing infants whose mothers are taking codeine and are ultra rapid metabolizers of codeine. When codeine enters the body and is metabolized, it changes to morphine, which relieves pain. Many factors affect codeine metabolism, including a person's genetic make up. Some people have a variation in a liver enzyme and may change codeine to morphine more rapidly and completely than other people. Nursing mothers taking codeine may also have higher morphine levels in their breast milk. These higher levels of morphine in breast milk may lead to life-threatening or fatal side effects in nursing babies. In most cases, it is not known if someone is an ultra rapid metabolizer of codeine. When prescribing codeine containing drugs to nursing mothers, it is recommended that the lowest effective dose be used for the shortest period of time. It is also recommended that the mother infant pairs be closely monitored. There is an FDA cleared test for determining a patient's CYP450 2D6 genotype. The test is not routinely used in clinical practice but is available through a number of different laboratories. The results of this test predict that a person can convert codeine to morphine at a faster rate than average, resulting in higher morphine levels in the blood. When levels of morphine are too high, patients have an increased risk of adverse events.

Use with caution in patients with asthma, COPD, emphysema, renal or liver dysfunction, cardiovascular disease, peptic ulcer, sleep apnea, seizures or hypertensive crisis.

Use with caution in patients with allergies to other opioid agonists.


Data not available