Dronabinol

 Action Principal psychoactive substance derived from cannabis (marijuana); mechanism by which it prevents nausea and vomiting is unknown.

 Indications Control of chemotherapy-induced nausea and vomiting unresponsive to other antiemetics; appetite stimulation in AIDS cachexia.

 Contraindications Hypersensitivity to marijuana or sesame oil.

 Route/Dosage

Antiemetic

ADULTS & CHILDREN: PO 5 mg/m2 1 to 3 hr before chemotherapy and q 2 to 4 hr after chemotherapy. Can give 4 to 6 doses/day and increase by 2.5 mg/m2/dose; do not exceed 15 mg/m2/dose.

Appetite Stimulation

ADULTS: PO 2.5 mg bid. Can give single daily dose of 2.5 mg to patients in whom adverse effects develop. Can increase by 2.5 mg/day; do not exceed 20 mg/day.

 Interactions

Amphetamines, cocaine, sympathomimetics: Hypertension; tachycardia. CNS depressants: Increased CNS adverse effects.

 Lab Test Interferences None well documented.

 Adverse Reactions

CV: Tachycardia; hypotension. CNS: Euphoria; dizziness; paranoid reaction; somnolence; seizures in patients with existing seizure disorders. OTHER: Tolerance, psychological and physical dependence with chronic use.

 Precautions

Pregnancy: Category B. Lactation: Excreted in breast milk. Children: Not recommended in children with AIDS cachexia. Elderly patients: More sensitive to psychoactive effects. Drug dependence: Drug has abuse potential.

 Administration/Storage

• When given as appetite stimulant, administer bid before lunch and supper.
• Refrigerate capsules; do not freeze.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies. Note history of drug or alcohol abuse.
• Assess for nausea, vomiting, appetite, bowel sounds and abdominal pain before and after drug is administered.
• Monitor BP and pulse rate during therapy, especially in patients with hypotension or cardiac disease.
• Monitor I&O, hydration, nutritional status and weight regularly.
• Monitor side effects, which vary with each patient and are usually dose related. Side effects may be exacerbated in elderly, manic, depressive or schizophrenic patients.
• Administer IV fluids as ordered for severe nausea and vomiting.
• Assess for signs of withdrawal syndrome, including: irritability, restlessness, insomnia, hot flashes, sweating, rhinorrhea, loose stools, hiccoughs, anorexia.
• Limit quantity of drug available to patient to amount necessary for single cycle of chemotherapy.
• Assist patient with ambulation. Implement safety measures (eg, side-rails) to prevent falls, especially in elderly patients.

 Patient/Family Education

• Instruct patient to take drug exactly as ordered by physician.
• Discuss psychoactive symptoms with patient and family. Symptoms may be minimized by providing quiet, supportive environment.
• Explain that signs of overdose (mood changes, confusion, hallucinations, depression, nervousness, fast or pounding heartbeat) may occur with increased doses.
• Instruct patient to make position changes slowly to prevent orthostatic hypotension.
• Advise patient and family that adult supervision is necessary as patient may experience drowsiness, dizziness, difficulty concentrating, and perceptual and coordination impairment.
• Instruct patient to avoid intake of alcoholic beverages, barbiturates and other CNS depressants.
• Advise patient that drug may cause drowsiness and to use caution while driving or performing other tasks requiring mental alertness.