Bexarotene (Targretin®), Oral Formulation

Bexarotene belongs to a class of medications called retinoids. Retinoids are relatives of vitamin A and appear to interfere with genes that control cell growth. The exact way bexarotene works is unknown, but it is believed to inhibit the growth of tumor cells.

How to Take Bexarotene

Bexarotene comes in a capsule form. The actual dose is based on your body size. Bexarotene should be taken with food, preferably at the same time each day. Do not chew, open, or break the capsules. If you miss a dose, call your care provider or pharmacist for instructions.

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.

The blood levels of this medication can be affected by certain foods and medications, so they should be avoided. These include: grapefruit, grapefruit juice, itraconazole, erythromycin, gemfibrozil, and ketoconazole. Be sure to tell your healthcare provider about all medications and supplements you take.

Safety Considerations When Receiving Bexarotene:

• Vitamin A supplements can worsen the side effects of bexarotene. The manufacturer recommends limiting vitamin A supplementation less than 15,000 IU/day, but you should discuss taking any vitamin supplements with your doctor BEFORE you take them.
• Bexarotene can cause harm to a fetus (unborn baby). Men and women should not become pregnant (or father a child). Two methods of effective contraception (one non-hormonal) are recommended for women of childbearing potential for one month before starting, during therapy, and one month after completing therapy. Discuss with your doctor when you may safely become pregnant after therapy. You may be instructed to start this medication on a certain day of your menstrual cycle.
• Men should use condoms during sexual activity during therapy and for one month after completing therapy to protect their partner from exposure to the medication and prevent them from becoming pregnant.

Storage and Handling

Store your medication in the original, labeled container at room temperature and in a dry location (unless otherwise directed by your healthcare provider or pharmacist). This medication should not be stored in a pillbox. Keep containers out of reach of children and pets.

If a caregiver prepares your dose for you, they should consider wearing gloves or pour the pills directly from their container into the cap, a small cup, or directly into your hand. They should avoid touching the pills. They should always wash their hands before and after giving you the medication. Pregnant or nursing women should not prepare the dose for you. Ask your oncology team where to return any unused medication for disposal. Do not flush down the toilet or throw in the trash.

Where do I get this medication?

Bexarotene oral formulation is available through retail/mail order pharmacy. Your oncology team will work with your prescription drug plan to identify an in-network, retail or mail order pharmacy for medication distribution.

Insurance Information

This medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals depending upon 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.

Possible Side Effects of Bexarotene

There are a number of things you can do to manage the side effects of bexarotene. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:

Increased Triglycerides and Cholesterol

This medication can increase the blood levels of triglycerides and cholesterol. Your healthcare team will routinely monitor your blood levels and treat the elevated levels as needed.

Thyroid Problems

This medication can cause hypothyroidism (underactive thyroid). Your healthcare provider will perform blood tests to check the function of your thyroid and treat this side effect if it develops. Symptoms of thyroid problems include: tiredness, feeling hot or cold, change in your voice, weight gain or loss, hair loss, and muscle cramps. Report any of these symptoms to your oncology care team.

Headache

Your healthcare provider can recommend medications and other strategies to help relieve pain.

Low White Blood Cell Count (Leukopenia or Neutropenia)

White blood cells (WBC) are important for fighting infection. While receiving treatment, your WBC count can drop, putting you at a higher risk of getting an infection. You should let your doctor or nurse know right away if you have a fever (temperature greater than 100.4°F or 38°C), sore throat or cold, shortness of breath, cough, burning with urination, or a sore that doesn't heal.

Tips to preventing infection:

• Washing hands, both yours and your visitors, is the best way to prevent the spread of infection.
• Avoid large crowds and people who are sick (i.e.: those who have a cold, fever, or cough or live with someone with these symptoms).
• When working in your yard, wear protective clothing including long pants and gloves.
• Do not handle pet waste.
• Keep all cuts or scratches clean.
• Shower or bathe daily and perform frequent mouth care.
• Do not cut cuticles or ingrown nails. You may wear nail polish, but not fake nails.
• Ask your oncology care team before scheduling dental appointments or procedures.
• Ask your oncology care team before you, or someone you live with has any vaccinations.

Important but Less Common Side Effects

• Sun Sensitivity: This medication can make your skin more sensitive to the sun, which can result in severe sunburn or rash. Sun sensitivity can last even after chemotherapy is completed. Avoid the sun between 10-2 pm, when it is strongest. Wear sunscreen (at least SPF 15) every day; wear sunglasses, a hat, and long sleeves/pants to protect your skin and seek out shade whenever possible.
• Liver Toxicity: This medication can cause liver toxicity, which your oncology care team may monitor for using blood tests called liver function tests. Notify your healthcare provider if you notice yellowing of the skin or eyes, your urine appears dark or brown, or you have pain in your abdomen, as these can be signs of liver toxicity.
• Pancreatitis: This medication can cause pancreatitis (inflammation of the pancreas). Symptoms include nausea, vomiting, and abdominal or back pain. Notify your care team or go to the emergency room if you experience any of these symptoms while taking bexarotene.
• Cataracts: This medication may increase the risk of developing cataracts. Report any changes in vision to your healthcare provider, including cloudy or blurry vision, difficulty seeing at night, sensitivity to light, seeing "halos" around lights, and/or yellowing of colors.
• Hypoglycemia: Diabetic patients who use insulin need to closely monitor their blood sugars as this medication can enhance the effectiveness of insulin. Symptoms of hypoglycemia include dizziness, feeling of hunger, headache, and confusion. Contact your care provider if you are experiencing hypoglycemia.

Reproductive Concerns

As mentioned above, exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant or father a child while on this medication. Effective birth control is necessary 1 month before starting therapy, during treatment, and for at least 1 month after treatment for women and for 1 month after treatment has ended for men. Even if your menstrual cycle stops or you believe you are not producing sperm, you could still be fertile and conceive. Women should use two forms of birth control, including one non-hormonal form. Men should use condoms. You should not breastfeed while taking this medication.