Promethazine hydrochloride - oral/IV/IM/suppository (Phenergan®)

How this Medication Comes

This medication comes as tablets, oral syrup, intramuscular (as a shot, IM), and intravenous (given in a vein, IV) formulations.

Promethazine can be given on as needed or scheduled basis and should be taken as prescribed by your provider. The dose and how often you take promethazine will depend on why you were prescribed it. You should not drink alcohol while taking promethazine. You should not drive a car or operate heavy machinery until you know how promethazine affects you.

This medication can be affected by certain foods and medications, so they should be avoided. Be sure to tell your healthcare provider about all medications and supplements you take including but not limited to: anticholinergic agents including aclidinium, glycopyrrolate, ipratropium, umeclidinium, tiotropium, metoclopramide, potassium supplement pills, and CNS depressants including buprenorphine and opioid pain medications.

It is important to make sure you are taking the correct amount of medication every time. Before every dose, check that what you are taking matches what you have been prescribed.

Storage and Handling

All oral versions (tablets, syrup) of promethazine should be stored in the original, labeled container at room temperature. The syrup version of promethazine should be in a light-protected bottle with the lid tightly closed at all times. Keep containers out of reach of children and pets.

Where do I get this medication?

The oral form of promethazine is available through retail/mail order pharmacy. Your oncology team will work with your prescription drug plan to identify an in-network retail/mail order pharmacy for medication distribution. You can work with your provider’s office if this medication needs a prior authorization. The intravenous or intramuscular form would be provided to you in a healthcare setting as ordered by your medical team.

Insurance Information

The oral form of this medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals without prescription drug coverage. Co-pay cards, which reduce the patient co-pay responsibility for eligible commercially (non-government sponsored) insured patients, may also be available. Your care team can help you find these resources, if they are available. Administration of the intravenous or intramuscular form in either the outpatient or inpatient setting would be covered under your medical benefits.

Possible Side Effects

This medication is given to manage and/or prevent side effects of your cancer treatment. If you are having side effects from this medication you should talk to your team about if this medication is necessary for your treatment or if there are other options to help manage the side effect this medication is treating. These are some of the most common side effects:

Reproductive Concerns

You should consult with your healthcare team prior to becoming pregnant, fathering a child, or breastfeeding while receiving this medication because fetal risk cannot be ruled out in these situations. Risk versus benefits should be weighed and discussed with your healthcare team.

Lower Seizure Threshold

Promethazine may lower seizure threshold. It should be used with caution in persons with seizure disorders or in persons who are using concomitant medications, such as pain medications or local anesthetics, which may also affect seizure threshold.

Bone-Marrow Suppression

Chronic use of promethazine may lower white blood cells and platelets in patients on cytotoxic chemotherapy. Your healthcare team will monitor your labs and adjust and hold this medication as necessary.