dronabinol

Dronabinol (Marinol) is a man-made compound that contains cannabinoids found in the marijuana plant (Cannabis sativa L). Dronabinol contains tetrahydrocannabinol (THC) in standardized concentrations and does not contain other compounds found in street marijuana that is not approved by the FDA for medical use.

Dronabinol activates cannabinoid receptors causing a wide range of effects in the brain, including short-term memory loss, euphoria, enhanced sensation, and increased appetite. It also prevents nausea and vomiting probably by inhibiting the vomiting center in the brain. Dronabinol was approved by the FDA in May 1985.

The most common side effects of dronabinol include

• weakness,
• palpitations,
• rapid heartbeat,
• facial flushing,
• abdominal pain,
• nausea,
• vomiting,
• anxiety,
• nervousness,
•  confusion,
• depersonalization,
• dizziness,
• euphoria,
• hallucinations,
• paranoid reaction, and
• abnormal thinking.

Less common side effects include

• low blood pressure,
• eye problems,
• diarrhea,
• fecal incontinence,
• muscle pain,
• depression,
• nightmares,
• speech problems,
• ringing in the ears (tinnitus), and
• flushing.

Dronabinol is a controlled substance because it may be abused.

For appetite stimulation in AIDS patients

• The general recommended starting dose is 2.5 mg by mouth twice daily, before lunch and dinner.
• Patients who are having difficulty tolerating this dosage may take 2.5 mg once a day in the evening or at bedtime.
• In patients who are tolerating dronabinol well, the dose may be slowly increased up to a maximum dose of 20 mg per day.

For nausea and vomiting

• 5 mg per meter-squared of body surface (5 mg/m2) should be administered 1-3 hours before chemotherapy followed by repeated administration every 2 to 4 hours after chemotherapy for a total of 4 to 6 doses per day.
• If needed, the dosage may be increased in 2.5 mg/m2 increments to a maximum of 15 mg/m2 per dose.

Although no drug-drug interactions were identified during clinical trials conducted by the manufacturer, dronabinol should be used cautiously with other medications that are known to interact with cannabinoids.

People taking dronabinol should not drink alcohol, smoke marijuana, take sedatives and hypnotics, or take other medicines that have an effect on the central nervous system. Examples of drugs to avoid include diazepam (Valium), chlordiazepoxide (Librium), alprazolam (Xanax), secobarbital (Seconal), pentobarbital (Nembutal), and phenobarbital.

There are no adequate and well-controlled studies evaluating the use of dronabinol during pregnancy. Dronabinol should only be used during pregnancy if the potential benefit to the mother justifies the potential risk to the unborn baby. Dronabinol is classified as FDA pregnancy risk category C. (Animal studies have shown adverse effects on the fetus, but there are no adequate studies in humans.)

Dronabinol is not recommended for use during breastfeeding because it is excreted into human milk and may have harmful effects on the nursing infant.

What preparations of dronabinol-oral are available?

Oral capsules: 2.5, 5, and 10 mg

How should I keep dronabinol-oral stored?

Dronabinol capsules should be stored in a cool location between 8 C and 15 C (46 F and 59 F ) or in the refrigerator. Capsules should not be frozen.