Dronabinol

(droh-nab-uh-nohl)

Trade/other name(s): Marinol

Why would this drug be used?

Dronabinol is used to treat nausea and vomiting following chemotherapy when the usual anti-nausea agents do not work.

How does this drug work?

Dronabinol is part of a class of drugs called cannabinoids. These drugs are useful for some patients in preventing nausea and vomiting. Dronabinol is also used to stimulate appetite. How it works is not known.

Before taking this medicine

Tell your doctor…

• If you are allergic to anything, including medicines, dyes, additives, or foods.
• If you have high blood pressure, heart disease, or fast heart rate. Dronabinol may worsen these problems.
• If you take any blood pressure medicines or have ever fainted. This drug may lower your blood pressure, which could be dangerous if it is already low, or if it is affected by other medicines.
• If you have serious mental health problems such as mania, depression, schizophrenia, or addictions. These conditions may be worsened by dronabinol.
• If you are pregnant, trying to get pregnant, or if there is any chance of pregnancy. Taking this drug during pregnancy may harm the fetus.
• If you are breast-feeding. Dronabinol is concentrated in breast milk and may harm the baby.
• About any other prescription or over-the-counter medicines you are taking, including vitamins and herbs. In fact, keeping a written list of each of these medicines (including the doses of each and when you take them) with you in case of emergency may help prevent complications if you get sick.

Interactions with other drugs

Dronabinol may cause drowsiness and dizziness, and change your perception of reality, which can affect activities such as driving. Other substances that can impair the brain can increase these effects during treatment with dronabinol, such as:

• anti-anxiety drugs, sedatives, or "nerve pills" such as diazepam (Valium), lorazepam (Ativan) alprazolam (Xanax), triazolam (Halcion)
• muscle relaxers (for muscle spasms and some types of back pain)
• antihistamines (allergy drugs)
• opioid pain medicines such as morphine or codeine
• anti-seizure medicines such as phenobarbital
• sleeping pills such as secobarbital, temazepam (Restoril), or flurazepam (Dalmane)
• alcohol

These drugs can seriously raise the heart rate and blood pressure if used with dronabinol:

• amphetamines or stimulants such as dextroamphetamine (Dexedrine) or methylphenidate (Ritalin) and others
• tricyclic antidepressants such as amitriptyline (Elavil), nortriptyline (Pamelor), desipramine (Norpramin), doxepin (Sinequan), and others)

Check with your doctor, nurse, or pharmacist about which medicines, vitamins, herbs, or supplements can cause problems with dronabinol.

Interactions with foods

Do not drink alcohol while taking dronabinol. Otherwise, no serious interactions with food are known at this time. Check with your doctor, nurse, or pharmacist about whether foods may be a problem.

Tell all the doctors, dentists, nurses, and pharmacists you visit that you are taking this drug.

How is this drug taken or given?

Dronabinol, a soft-gel capsule that is usually taken 1 to 3 hours before chemotherapy, then again 2 to 4 hours after chemotherapy as directed. After that, it may be taken as needed every few hours. Your doctor or nurse will choose your dose based your size and whether you have any side effects. If you have no side effects but still have some nausea, the dose will be increased by your doctor.

This drug should be taken exactly as directed by your physician. If you don't understand the instructions or side effects, talk to your doctor or nurse.

Store the medicine in a tightly closed container away from heat and moisture and out of the reach of children and pets. It can be refrigerated, but not frozen. Do not allow others to share your medicines.

Precautions

This medicine can cause drowsiness and lightheadedness. Do not drive, operate machinery, or perform other activities that require alertness and good judgment while taking this medicine. These symptoms may be worse in older people.

Be careful getting up, changing position, or walking. This drug may cause low blood pressure, which can make you feel dizzy or faint. Get up slowly and hold onto something or someone to keep you steady. Let your doctor know if you have this problem.

Dronabinol can distort your perceptions and sense of reality, which can impair your thinking and judgment. Have a responsible adult with you for a few days after starting dronabinol, and after any increase in dose, until you have adjusted to the medicine.

Since dronabinol affects the central nervous system, it is important not to take other drugs or substances that slow down the brain or nervous system such as alcohol, sedatives, muscle relaxers, and sleeping pills unless your doctor tells you to do so.

Dronabinol can also produce psychological dependence, which can lead to addiction. Some signs of psychological dependence are a strong desire to keep taking the medicine and wanting more or larger doses of the medicine. Talk with your doctor if you think this is happening to you.

People who took high doses of dronabinol each day for 12-16 days noticed symptoms when they stopped taking it, such as irritability, restlessness, sleeplessness, hot flashes, diarrhea, hiccups, runny nose, and poor appetite. Most of these symptoms were gone within about 3 days, although sleep was disturbed for a few weeks. Take dronabinol only as directed by your doctor.

Call your doctor or nurse right away if you notice confusion, seizures, fainting, trouble walking or moving, fast or pounding heartbeat, seeing or hearing things that aren’t there, or other serious side effects. These effects can last for up to a day or two after the last dose.

Possible side effects

You will probably not have most of the following side effects, but if you have any talk to your doctor or nurse. They can help you understand the side effects and cope with them.

Common

• mood changes (anxiety, depression, paranoia, euphoria, apathy, and more)*
• confusion, disorientation
• drowsiness*
• muddled thinking, trouble concentrating, poor memory
• dizziness
• change in ability to perceive surroundings
• feeling "unreal" (depersonalization)
• poor coordination
• unsteady walking*
• dry mouth
• increased appetite
• low energy

Less common

• increased heart rate (palpitations)
• dizziness due to low blood pressure when sitting or standing up*
• nightmares
• paranoia (fearfulness)
• red eyes
• feeling "high"

Rare

• seizures*
• seeing or hearing things that aren't there (hallucinations)*
• physical and psychological dependence*

*See "Precautions" section for more detailed information.

There are some other side effects not listed above that can also occur in some patients. Tell your doctor or nurse if you develop these or any other problems.

FDA approval

Yes – first approved in 1985.

Disclaimer: This information does not cover all possible uses, actions, precautions, side effects, or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for talking with your doctor, who is familiar with your medical needs.