Promethazine Oral

In Depth

severe muscle stiffness
mental/mood changes (e.g., sudden confusion, extreme drowsiness)
very high fever
seizures
irregular/fast heartbeat
increased sweating

A very serious allergic reaction to this drug is unlikely, but stop taking this medication and seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include:

rash
itching/swelling (especially of the face/tongue/throat)
severe dizziness
trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Promethazine Oral Precautions

See also Warning section.

Before taking promethazine, tell your doctor or pharmacist if you are allergic to it; or to any other phenothiazines (e.g., prochlorperazine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

This medication should not be given to a person who is unconscious.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have:

certain lung/breathing problems (e.g., asthma, chronic obstructive pulmonary disease-COPD, sleep apnea)

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

blood/immune system problems (e.g., bone marrow depression)
a certain eye problem (narrow-angle glaucoma)
heart disease (e.g., angina, irregular heartbeat)
high blood pressure
liver disease
certain nervous system problems (e.g., neuroleptic malignant syndrome, Reye's syndrome)
seizure
stomach/bowel problems (e.g., blockage, ulcer disease)
sun sensitivity when using other medications
urination problems (e.g., due to enlarged prostate, blockage)