home > drugs a-z list > phenergan (promethazine) drug center > phenergan (promethazine) drug

Recommended Topic Related To:

Phenergan

Allergy facts

  • Allergy involves an exaggerated response of the immune system.
  • The immune system is the body's organized defense mechanism against foreign invaders, particularly infections.
  • Allergens are substances that are foreign to the body and can cause an allergic reaction.
  • IgE is the allergy antibody.
  • Allergies can develop at any age.
  • Your risk of developing allergies is related to your parents' allergy history.

Introduction

In this review you will learn how allergy relates to the immune system. You will begin understanding how and why certain people become allergic. The most common allergic diseases are discussed briefly in this article.

What does an allergy mean?

An allergy refers to an exaggerated reaction by our immune system in response to bodily contact with certain foreign substances. It is exaggerated because these f...

Phenergan

font size
Discontinued Warning IconPlease Note: This Brand Name drug is no longer available in the US.
(Generic versions may still be available.)

Phenergan®
(promethazine HCI)
Tablets and Suppositories

DRUG DESCRIPTION

Each tablet of Phenergan contains 12.5 mg, 25 mg, or 50 mg promethazine HCl. The inactive ingredients present are lactose, magnesium stearate, and methylcellulose. Each dosage strength also contains the following:

12.5 mg-FD&C Yellow 6 and saccharin sodium;
25 mg-saccharin sodium;
50 mg-FD&C Red 40.

Each rectal suppository of Phenergan contains 12.5 mg, 25 mg, or 50 mg promethazine HCl with ascorbyl palmitate, silicon dioxide, white wax, and cocoa butter. Phenergan (promethazine) Suppositories are for rectal administration only.

Promethazine HCl is a racemic compound; the empirical formula is C17H20N2S•HCl and its molecular weight is 320.88.

Promethazine HCl, a phenothiazine derivative, is designated chemically as 10H-Phenothiazine-10-ethanamine, N,N,alpha;-trimethyl-, monohydrochloride, (±)- with the following structural formula:

Phenergan (promethazine HCI) structural formula illustration

Promethazine HCl occurs as a white to faint yellow, practically odorless, crystalline powder which slowly oxidizes and turns blue on prolonged exposure to air. It is freely soluble in water and soluble in alcohol.

What are the possible side effects of oral promethazine (Pentazine, Phenergan)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using promethazine and call your doctor at once if you have any of these serious side effects:

  • twitching, or uncontrollable movements of your eyes, lips, tongue, face, arms, or legs;
  • tremor (uncontrolled shaking), drooling, trouble swallowing, problems with balance or walking;
  • feeling restless, jittery, or agitated;
  • ...

Read All Potential Side Effects and See Pictures of Phenergan »

What are the precautions when taking promethazine (Phenergan)?

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:...

Read All Potential Precautions of Phenergan »

Last reviewed on RxList: 6/21/2007
This monograph has been modified to include the generic and brand name in many instances.

Phenergan - User Reviews

Phenergan User Reviews

Now you can gain knowledge and insight about a drug treatment with Patient Discussions.

Here is a collection of user reviews for the medication Phenergan sorted by most helpful. Patient Discussions FAQs

Report Problems to the Food and Drug Administration

 

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.


Allergies & Asthma

Improve treatments & prevent attacks.