promethazine and codeine, Phenergan with Codeine (cont.)

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Medical and Pharmacy Editor:

There may be an increase in the risk of certain neurologic reactions that affect movement of muscles (EPS, see below) when promethazine is combined with medicines that also cause EPS. Such drugs include antipsychotics, metoclopramide (Metozolv ODT, Reglan), and amoxapine.

Promethazine should not be used with propylthiouracil (PTU) due to the increased risk of low white blood cell counts and increased risk of infections. The reason for this interaction is not known.

Concurrent use of promethazine with the dye used for myelography (X-rays of the spinal cord) can lower the threshold for seizures and thus increase the risk of seizures. Promethazine should be stopped at least 48 hours before myelography and not restarted until at least 24 hours after myelography.

PREGNANCY: There are no adequate studies of promethazine and codeine in pregnant women. Administration of promethazine within two weeks of delivery may affect platelet function in the newborn. Codeine generally is avoided during pregnancy because it may cause fetal physical dependence, withdrawal and growth retardation.

NURSING MOTHERS: It is not known if promethazine is excreted in breast milk. Small amounts of codeine are secreted in breast milk, but the risk of adverse events in the infant is small.

SIDE EFFECTS: The most common side effects of codeine are:

Codeine is habit forming. Mental and physical dependence can occur but are unlikely when used for short-term pain relief. If codeine is suddenly withdrawn after prolonged use, symptoms of withdrawal may develop. The dose of codeine should be reduced gradually in order to avoid withdrawal symptoms.

Important side effects of promethazine include anticholinergic side effects such as:

Medically Reviewed by a Doctor on 11/26/2014


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