Nabilone (Monograph)

Brand name: Cesamet
Drug class: Cannabinoids

Medically reviewed by Drugs.com on May 10, 2024. Written by ASHP.

Introduction

Antiemetic; a synthetic cannabinoid.^{1 2 6 15}

Uses for Nabilone

Cancer Chemotherapy-induced Nausea and Vomiting

Prevention of nausea and vomiting associated with cancer chemotherapy in patients who have failed to respond adequately to conventional antiemetic therapy.^{1 2 3 4 5 8 10 11 15}

ASCO does not consider cannabinoids (e.g., nabilone, dronabinol) appropriate first-line antiemetics for patients receiving chemotherapy of low, moderate, or high emetic risk.¹⁶ For patients in whom a cannabinoid is chosen for rescue or refractory antiemetic use, ASCO recommends nabilone or dronabinol over medical marijuana and states that dosage regimens for these synthetic cannabinoids are well established; however, such information is not available for the various preparations of medical marijuana.¹⁶

Nabilone Dosage and Administration

Administration

Oral Administration

Administer orally without regard to meals.^{1 2 5} Has been administered IV; however, a parenteral preparation is not commercially available in the US.^{1 2 6}

Dosage

Adults

Cancer Chemotherapy-induced Nausea and Vomiting

Oral

Usual dosage: 1 or 2 mg twice daily; administer initial dose 1–3 hours before chemotherapy.^{1 2} May be administered 2 or 3 times daily during the entire chemotherapy cycle and, if needed, for 48 hours after the last dose of chemotherapy in each cycle.^{1 2}

Initiate with the lower dosage (i.e., 1 mg twice daily) to minimize adverse effects, then increase dosage as necessary up to a maximum of 2 mg 3 times daily.^{1 2}

May administer a dose of 1 or 2 mg the night prior to chemotherapy.^{1 2}

Prescribing Limits

Adults

Cancer Chemotherapy-induced Nausea and Vomiting

Oral

Maximum: 2 mg 3 times daily.^{1 2}

Special Populations

Hepatic Impairment

No specific dosage recommendations at this time.¹

Renal Impairment

No specific dosage recommendations at this time.¹

Geriatric Patients

Select dosage with caution, usually initiating at the lower end of the recommended dosage range because of possible age-related decreases in hepatic, renal, and/or cardiac function; concomitant diseases and drug therapy; and possible increased sensitivity to adverse effects.¹ (See Geriatric Use under Cautions.)

Cautions for Nabilone

Contraindications

Hypersensitivity to any cannabinoid.^{1 2}

Warnings/Precautions

Warnings

Effects of nabilone may persist for a variable and unpredictable period of time following oral administration.^{1 2 3 5 12}

CNS Effects

CNS effects, including dizziness, drowsiness or sedation, euphoria (i.e., “high”), ataxia, anxiety, disorientation, depression, hallucinations, and psychosis, reported.^{1 2 4 5 6 7 8 12 18} Adverse psychiatric reactions can persist for 48–72 hours following discontinuance of nabilone.^{1 2 5 12} Exacerbation of psychosis reported in a 70-year-old woman with parkinsonian syndrome following ingestion of two 1-mg doses of nabilone.¹⁸

Individual response and tolerance may vary; a responsible adult should supervise patients, particularly during initial therapy and during dosage adjustments.^{1 2}

Cardiovascular Effects

May cause tachycardia and orthostatic hypotension.^{1 2 3 4 5 6 8 12} Elevations in supine and standing heart rates also reported.^{1 2 3 4 5 6 8 12}

Individual response and tolerance may vary; a responsible adult should supervise patients, particularly during initial therapy and during dosage adjustments.^{1 2} Carefully evaluate the potential risks and benefits of the drug; use with caution in geriatric patients and in patients with hypertension and/or cardiovascular disease.^{1 2 4 12} (See Geriatric Use under Cautions.)

General Precautions

Psychiatric Disorders

Use with caution in patients with current or history of psychiatric disorders (e.g., bipolar disorder, depression, schizophrenia); cannabinoid use may unmask the symptoms of these diseases.^{1 2}

Abuse Potential

Marijuana contains an active compound similar to nabilone.^{1 2} Use nabilone with caution in patients with history of substance abuse, including alcohol abuse or dependence and marijuana use.^{1 2} Increased risk of substance abuse in patients with personal or family history of substance abuse or mental illness.^{1 2} Monitor patients receiving nabilone for signs of excessive use, abuse, and misuse.^{1 8 12}

High potential for abuse.^{1 2} Limit prescriptions to quantity necessary for a single cycle of chemotherapy (i.e., a few days);^{1 2} not intended for use on an as-needed basis or as the initial prescribed antiemetic therapy.^{1 2 15}

Specific Populations

Pregnancy

Category C.^{1 2}

Lactation

Not known whether nabilone is distributed into milk.^{1 2} Avoid use in nursing women.^{1 2}

Pediatric Use

Safety and effectiveness not established.^{1 2} Caution is advised because of psychoactive effects.^{1 2}

Geriatric Use

Insufficient experience in patients ≥65 years of age to determine whether they respond differently than younger adults.^{1 2} Use with caution because of increased sensitivity to psychoactive effects and risk of elevated supine and standing heart rates and postural hypotension.^{1 2 12}

Hepatic Impairment

Not studied in patients with hepatic impairment.^{1 2}

Renal Impairment

Not studied in patients with renal impairment.^{1 2}

Common Adverse Effects

Adverse effects may be similar to those of marijuana (cannabis) and other cannabinoids.^{1 2 12 13}

Drowsiness, vertigo, dry mouth, ataxia, euphoria (i.e., feeling “high”), dysphoria, sleep disturbances, headache.^{1 2 4 5 6 7 8 12 13}

Drug Interactions

Nabilone is a synthetic cannabinoid; interactions reported with Cannabis sativa L (marijuana) also may occur with nabilone.^{1 2}

Extensively metabolized by multiple CYP isoenzymes.^{1 2}

Does not substantially inhibit CYP isoenzymes 1A2, 2A6, 2C19, 2D6, and 3A4; weak inhibitor of CYP 2E1 and 3A4 isoenzymes and a moderate inhibitor of CYP 2C8 and 2C9 isoenzymes.^{1 2}

Drugs Metabolized by Hepatic Microsomal Enzymes

Inhibitors or inducers of CYP isoenzymes: possible altered nabilone metabolism.^{1 2}

Pharmacokinetic interaction with drugs metabolized by CYP isoenzymes unlikely because very low plasma nabilone concentrations are achieved with clinical use.^{1 2}

Protein-bound Drugs

Possible displacement of other protein-bound drugs.^{1 2} Monitor patients and adjust dosages as necessary.^{1 2}

Specific Drugs

Nabilone Pharmacokinetics

Absorption

Bioavailability

Appears to be completely absorbed from the GI tract after oral administration, with peak plasma concentrations achieved within 2 hours.¹

Food

Food does not appear to significantly affect the rate or extent of absorption.¹

Distribution

Extent

Volume of distribution: Approximately 12.5 L/kg.¹

Elimination

Metabolism

Extensively metabolized, including metabolism via multiple CYP isoenzymes, to several metabolites; relative pharmacologic activities of the metabolites and the parent drug not established.^{1 2}

Elimination Route

Following IV administration, nabilone and its metabolites are eliminated principally in feces (approximately 67%) and to a lesser extent in urine (approximately 22%) within 7 days.^{1 2}

Following oral administration, about 60% of nabilone and its metabolites were recovered in feces and about 24% in urine.^{1 2} The principal excretory pathway appears to be the biliary system.^{1 2}

No substantial accumulation of nabilone observed after chronic oral administration, but metabolites may accumulate at concentrations in excess of the parent drug with repeated administration.^{1 2}

Half-life

Approximately 2 hours.¹

Plasma half-life of total radioactivity (identified and unidentified metabolites) is approximately 35 hours.¹

Stability

Storage

Oral

Capsules

25°C (may be exposed to 15–30°C).¹

Actions

• Exerts complex effects on CNS.^{1 2 6 12 15}

• Antiemetic effect may be caused by interaction with the cannabinoid receptor system, including the cannabinoid 1 (CB₁) receptors in the central and peripheral nervous system.^{1 2 12 15}

• Binds to cannabinoid 2 (CB₂) receptors in the spleen and other peripheral tissues, which may play a role in the immunosuppressive effects of cannabinoids.^{2 12 15}

• Like other cannabinoids, may possess analgesic, antispasmodic, and muscle relaxant activity; however, further evaluation is necessary.^{2 10 15}

Advice to Patients

• Risk of additive or synergistic CNS depression during concurrent use with alcohol or other CNS depressants, including benzodiazepines and barbiturates.^{1 2} Importance of avoiding alcohol and other CNS depressants during nabilone therapy.^{1 2}

• Importance of avoiding driving, operating machinery, or performing hazardous tasks during nabilone therapy.^{1 2}

• Importance of informing patients about possible changes in mood and other adverse behavioral effects of nabilone to avoid panic if such manifestations occur.¹

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as concomitant illnesses.¹

• Importance of informing patients that they should remain under the supervision of a responsible adult during therapy.^{1 2}

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.¹

• Importance of informing patients of other important precautionary information.^{1 2} (See Cautions.)

Additional Information

The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer’s labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Subject to control under the Federal Controlled Substances Act of 1970 as a schedule II (C-II) drug.^{1 2}

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