What is the recommended dosing frequency for Phenergan (promethazine)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: February 16, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

The administration frequency of Phenergan (promethazine) is typically every 4 to 6 hours as needed.

Key Considerations

  • For adults, a typical dose of 12.5 to 25 milligrams may be administered orally every 4 to 6 hours as needed, not to exceed 100 milligrams in a 24-hour period 1.
  • The dosing frequency is supported by the medication's duration of action, which is 4 to 6 hours 1.
  • It is essential to consider the indication and patient population when determining the administration frequency of Phenergan (promethazine) 1.

Important Details

  • The clinical effects of promethazine are evident within 5 minutes of intravenous administration, and its plasma half-life is 9 to 16 hours 1.
  • Promethazine may be administered via different routes, including orally, intravenously, or per rectally, with varying dosages and administration frequencies 1.
  • The use of promethazine may require a reduction in the dosage of standard sedation agents, and its administration should be done with caution, especially in certain patient populations, such as older adults or those with a history of substance abuse 1.

From the Research

Dosing Frequency for Phenergan (Promethazine)

The recommended dosing frequency for Phenergan (promethazine) is not explicitly stated in the provided studies. However, the following information can be gathered:

  • The study 2 mentions that the maximum dose of promethazine was 50/25/25 mg, respectively, in a mixture with meperidine and chlorpromazine, but it does not provide information on the dosing frequency.
  • The study 3 discusses the risks of promethazine-induced thrombophlebitis when administered intravenously, but it does not provide information on the recommended dosing frequency.
  • The study 4 examines the pharmacokinetics of promethazine after administration of rectal suppositories and oral syrup, but it does not provide information on the recommended dosing frequency.
  • The studies 5 and 6 are not relevant to the question as they discuss different medications (fremanezumab and metoclopramide, respectively).

Key Points

  • The provided studies do not offer explicit guidance on the recommended dosing frequency for Phenergan (promethazine).
  • The study 2 suggests a maximum dose of 50 mg, but the dosing frequency is not specified.
  • The study 4 provides information on the pharmacokinetics of promethazine, but it does not address the dosing frequency.
  • Further research may be necessary to determine the recommended dosing frequency for Phenergan (promethazine).

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.