Promethegan is a rectal suppository containing the active ingredient promethazine HCl. Promethazine HCl is a phenothiazine derivative and is commonly used as an antihistamine. It is available in 12.5 mg and 25 mg doses and is intended for rectal administration. Key inactive ingredients in the suppositories include ascorbyl palmitate, cocoa butter, colloidal silicon dioxide, and white wax. Promethegan is designed for symptoms of allergic reactions by blocking histamine and can also calm the nervous system to alleviate nausea and vomiting.

How should I use this medication?

This medication is for rectal use only. Do not take by mouth. Wash your hands before and after use. Take off the foil wrapping. Wet the tip of the suppository with cold tap water to make it easier to use. Lie on your side with your lower leg straightened out and your upper leg bent forward toward your stomach. Lift upper buttock to expose the rectal area. Apply gentle pressure to insert the suppository completely into the rectum, pointed end first. Hold buttocks together for a few seconds. Remain lying down for about 15 minutes to avoid having the suppository come out. Do not use more often than directed.

Talk to your care team about the use of this medication in children. Special care may be needed. This medication should not be given to infants and children younger than 2 years old.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, use it as soon as you can. If it is almost time for your next dose, use only that dose. Do not use double doses.

Where should I keep my medication?

Keep out of the reach of children.

Store in a refrigerator between 2 and 8 degrees C (36 and 46 degrees F). Throw away any unused medication after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

• Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
• CNS depression—slow or shallow breathing, shortness of breath, feeling faint, dizziness, confusion, trouble staying awake
• High fever stiff muscles, increased sweating, fast or irregular heartbeat, and confusion, which may be signs of neuroleptic malignant syndrome
• Infection—fever, chills, cough, or sore throat
• Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
• Seizures
• Sudden eye pain or change in vision such as blurry vision, seeing halos around lights, vision loss
• Trouble passing urine
• Uncontrolled and repetitive body movements, muscle stiffness or spasms, tremors or shaking, loss of balance or coordination, restlessness, shuffling walk, which may be signs of extrapyramidal symptoms (EPS)

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

• Confusion
• Constipation
• Dizziness
• Drowsiness
• Dry mouth
• Sensitivity to light
• Vivid dreams or nightmares

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

• Blockage in your bowels
• Diabetes
• Glaucoma
• Have trouble controlling your muscles
• Heart disease
• Liver disease
• Low blood cell levels (white cells, red cells, and platelets)
• Lung or breathing disease, such as asthma
• Parkinson disease
• Prostate disease
• Seizures
• Stomach or intestine problems
• Trouble passing urine
• An unusual or allergic reaction to promethazine, sulfites, other medications, foods, dyes, or preservatives
• Pregnant or trying to get pregnant
• Breastfeeding

What may interact with this medication?

• Alcohol
• Antihistamines for allergy, cough, and cold
• Atropine
• Certain medications for anxiety or sleep
• Certain medications for bladder problems, such as oxybutynin or tolterodine
• Certain medications for depression, such as amitriptyline, fluoxetine, sertraline
• Certain medications for Parkinson disease, such as benztropine or trihexyphenidyl
• Certain medications for seizures, such as phenobarbital, primidone, phenytoin
• Certain medications for stomach problems, such as dicyclomine, hyoscyamine
• Certain medications for travel sickness, such as scopolamine
• Epinephrine
• General anesthetics, such as halothane, isoflurane, methoxyflurane, propofol
• Ipratropium
• MAOIs, such as Marplan, Nardil, and Parnate
• Medications for blood pressure
• Medications that relax muscles for surgery
• Metoclopramide
• Opioids

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress. Tell your care team if your symptoms do not start to get better or if they get worse.

This medication may affect your coordination, reaction time, or judgment. Do not drive or operate machinery until you know how this medication affects you. Sit up or stand slowly to reduce the risk of dizzy or fainting spells. Drinking alcohol with this medication can increase the risk of these side effects.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy and drinking plenty of water may help. Contact your care team if the problem does not go away or is severe.

This medication may cause dry eyes and blurred vision. If you wear contact lenses, you may feel some discomfort. Lubricating eye drops may help. See your care team if the problem does not go away or is severe.

This medication can make you more sensitive to the sun. Keep out of the sun. If you cannot avoid being in the sun, wear protective clothing and sunscreen. Do not use sun lamps, tanning beds, or tanning booths.

This medication may increase blood sugar. The risk may be higher in patients who already have diabetes. Ask your care team what you can do to lower your risk of diabetes while taking this medication.

What are the most serious risks of this medication?

This drug should not be given to infants or children younger than 2 years old. Use with caution in children older than 2 years of age. This drug may cause breathing to slow or stop in children. Children who have lung disease, asthma, or sleep apnea, or who use medicines for pain, sleep, or anxiety may be more at risk. Get emergency medical treatment if your child has unusual drowsiness, breathing problems, wheezing, pauses in breathing, or stops breathing.