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Phenadoz (rectal)

Generic name: promethazine (rectal) [ pro-METH-a-zeen ]
Brand names: Phenergan, Promethegan, Phenadoz rectal
Drug classes: Antihistamines, Phenothiazine antiemetics

Medically reviewed by on Aug 14, 2023. Written by Cerner Multum.

What is Phenadoz rectal?

Phenadoz is used to treat allergy symptoms such as itching, runny nose, sneezing, itchy or watery eyes, hives, and itchy skin rashes.

Phenadoz also prevents motion sickness, and treats nausea and vomiting or pain after surgery. It is also used as a sedative or sleep aid.

Phenadoz is not for use in treating symptoms of asthma, pneumonia, or other lower respiratory tract infections.

Phenadoz may also be used for other purposes not listed in this medication guide.

Phenadoz rectal side effects

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

Phenadoz may cause serious side effects. Call your doctor at once if you have:

Common side effects of Phenadoz may include:

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.


Phenadoz should not be given to a child younger than 2 years old. This medicine can cause severe breathing problems or death in very young children.

Before taking this medicine

Phenadoz should not be used in a child younger than 2 years old. This medicine can cause severe breathing problems or death in a child younger than 2. Carefully follow your doctor's instructions when giving Phenadoz to a child of any age.

You should not use this medicine if you are allergic to Phenadoz or to similar medicines such as chlorpromazine, fluphenazine, mesoridazine, perphenazine, prochlorperazine, thioridazine, or trifluoperazine.

Tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breastfeeding.

How should I use Phenadoz rectal?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Do not take Phenadoz by mouth. It is for use only in your rectum.

Try to empty your bowel and bladder just before using the Phenadoz suppository.

Remove the outer wrapper from the suppository before inserting it. Avoid handling the suppository too long or it will melt in your hands.

For best results from the suppository, lie down after inserting it and hold in the suppository for a few minutes. The suppository will melt quickly once inserted and you should feel little or no discomfort while holding it in. Avoid using the bathroom just after you have inserted the suppository.

Call your doctor if your symptoms do not improve, or if they get worse while using Phenadoz.

This medicine can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using Phenadoz.

Store the rectal suppositories in the refrigerator but do not allow them to freeze.

What happens if I miss a dose?

Use the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include overactive reflexes, loss of coordination, severe drowsiness or weakness, fainting, dilated pupils, weak or shallow breathing, or seizure (convulsions).

What should I avoid while using Phenadoz rectal?

Phenadoz may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Drinking alcohol can increase certain side effects of promethazine.

Avoid exposure to sunlight or tanning beds. Phenadoz can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

What other drugs will affect Phenadoz rectal?

Using Phenadoz with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Other drugs may affect Phenadoz, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use.

Frequently asked questions

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.