Promethazine
A phenothiazine derivative with strong antihistaminic and sedative properties.
Dosage by Body Weight
Boxed Warning: Do not use in children under 2 years due to potential for fatal respiratory depression.
- Body Weight
- Over 10 kg (Age >2y)
- Dose
- 0.25 mg/kg to 0.5 mg/kg
- Frequency
- As needed (max 3-4 times daily)
- Tracking Notes
- Highly sedative; monitor breathing closely.
| Body Weight | Dose | Frequency | Tracking Notes |
|---|---|---|---|
| Over 10 kg (Age >2y) | 0.25 mg/kg to 0.5 mg/kg | As needed (max 3-4 times daily) | Highly sedative; monitor breathing closely. |
Formulation
Purpose
Antihistamine used for allergy relief, nausea, motion sickness, and sedation.
Generic Name
Promethazine HydrochlorideBranded Drug Names
Promethazine is listed as a generic drug name. Common branded medicines that may contain the same active ingredient include:
Scheduled Drug
Yes. This medicine should be supplied or used only according to applicable prescription and regulatory requirements.
Alternatives
Safety Advice
Alcohol
UNSAFEPromethazine: Alcohol can worsen drowsiness, mood changes, impaired judgment, or heart rhythm effects. Avoid alcohol unless your prescriber confirms it is safe.
Pregnancy
CAUTIONPromethazine: Use in pregnancy only when prescribed after weighing mental health benefits and medicine-specific risks.
Breast Feeding
CAUTIONPromethazine: May pass into breast milk. Use while breastfeeding only with specialist guidance and infant monitoring.
Driving
CAUTIONPromethazine: May cause sleepiness, dizziness, slowed reaction time, or concentration changes. Avoid driving if affected.
Liver
CAUTIONPromethazine: Use caution in liver disease because several psychiatric or sedating medicines are processed by the liver.
Kidney
CAUTIONPromethazine: Kidney disease may require monitoring or dose adjustment for some medicines in this group.