Promethazine Dosing: An Introduction
The dose of
promethazine hydrochloride (
Phenergan®) your healthcare provider recommends will vary, depending on a number of factors, including:
- The medical condition being treated
- Your age and weight (for children)
- Other medications you may be taking
- Other medical conditions you may have.
As is always the case, do not adjust this amount unless your healthcare provider specifically instructs you to do so.
It should be noted that this article applies only to products that contain just promethazine as the active ingredient. Some promethazine cough syrups (such as Phenergan with Codeine) contain other active ingredients as well.
Dosage of Promethazine for Allergies
The standard recommended promethazine dose for treating
allergies is 25 mg (in tablet, rectal suppository, or syrup form) before bedtime. If necessary, smaller, more frequent amounts can be given (ranging from 6.25 to 12.5 mg three times daily).
When treating allergic reactions (such as reactions to blood transfusions), a typical dosage is 25 mg (in tablet, rectal suppository, syrup, or injection form). This may be repeated within two hours if necessary.
Promethazine Dose for Motion Sickness
The recommended dosage of promethazine for treating motion sickness in adults is 25 mg (in tablet, rectal suppository, or syrup form) twice daily.
On the first day of travel, the first dose should be taken 30 to 60 minutes before the anticipated travel, and the second one should be taken 8 to 12 hours later, if necessary.
On subsequent days of travel, the first dose should be taken right after getting up in the morning, and the second one should be taken before the evening meal.
A similar regimen is recommended for children, except with a lower dose (promethazine 12.5 to 25 mg twice daily).