Drug information of Dronabinol

Dronabinol (synthetic delta-9-tetrahydrocannabinol [delta-9-THC]), an active cannabinoid and natural occurring component of Cannabis sativa L. (marijuana), activates cannabinoid receptors CB1 and CB2. Activation of the CB1 receptor produces marijuana-like effects on psyche and circulation, whereas activation of the CB2 receptor does not. Dronabinol has approximately equal affinity for the CB1 and CB2 receptors; however, efficacy is less at CB2 receptors. Activation of the cannabinoid system with dronabinol causes psychological effects that can be divided into 4 groups: affective (euphoria and easy laughter); sensory (increased perception of external stimuli and of the person's own body); somatic (feeling of the body floating or sinking in the bed); and cognitive (distortion of time perception, memory lapses, difficulty in concentration). Most effects (eg, analgesia, appetite enhancement, muscle relaxation, hormonal actions) are mediated by central cannabinoid receptors (CB1), their distribution reflecting many of the medicinal benefits and adverse effects 

Absorption
Oral: 90% to 95%; 10% to 20% of dose reaches systemic circulation
Metabolism
Extensive first-pass hepatic primarily via microsomal hydroxylation to metabolites, some of which are active; 11-hydroxy-delta-9-tetrahydrocannabinol (11-OH-THC) is the major active metabolite
Excretion
Feces (50%, <5% as unchanged drug); urine (10% to 15%
Onset of Action
0.5
 to 1 hour; Peak effect: 2 to 4 hours
Time to Peak
Serum: 0.5 to 4 hours
Duration of Action
4 
to 6 hours (psychoactive effects); ≥24 hours (appetite stimulation
Half-Life Elimination
Biphasic: Alpha: 4 to 5 hours; Terminal: 25 to 36 hours

Anorexia in patients with AIDS: Treatment of anorexia associated with weight loss in patients with AIDS

Chemotherapy-induced nausea and vomiting: Treatment of nausea and vomiting associated with cancer chemotherapy in patients who have failed to respond adequately to conventional antiemetic treatments

Usual Adult Dose for Nausea/Vomiting - Chemotherapy Induced
Oral solution
Initial dose: 4.2 mg/m2 orally 1 to 3 hours prior to chemotherapy administration, then every 2 to 4 hours after chemotherapy for a total of 4 to 6 doses a day
Maintenance dose: May escalate dose by 2.1 mg/m2 increments during a chemotherapy cycle or at subsequent cycles if the initial dose is ineffective and there are no significant side effects
Maximum dose: 12.6 mg/m2 per dose
Oral tablets:
Initial dose: 5 mg/m2 orally 1 to 3 hours prior to chemotherapy administration, then every 2 to 4 hours after chemotherapy for a total of 4 to 6 doses a day
Maintenance dose: May escalate dose by 2.5 mg/m2 increments during a chemotherapy cycle or at subsequent cycles if the initial dose is ineffective and there are no significant side effects
Maximum dose: 15 mg/m2 per dose
Usual Adult Dose for Anorexia
Oral solution
Initial dose: 2.1 mg orally 2 times a day 1 hour before lunch and dinner; reduce dose to 2.1 mg orally once a day 1 hour before dinner or at bedtime for patients unable to tolerate 4.2 mg/day
-Maintenance dose: May increase dose to 2.1 mg/day or 4.2 mg/day orally (2.1 mg 1 hour before lunch and 4.2 mg 1 hour before dinner OR 4.2 mg 1 hour before lunch and 4.2 mg 1 hour before dinner) when adverse effects are absent/minimal or when further therapeutic effect is desired
Maximum dose: 16.8 mg/day (8.4 mg orally 2 times a day
Oral tablets
Initial dose: 2.5 mg orally 2 times a day 1 hour before lunch and dinner; reduce dose to 2.5 mg orally once a day 1 hour before dinner or at bedtime for patients unable to tolerate 5 mg/day
Maintenance dose: May increase dose to 7.5 mg/day or 10 mg/day orally (2.5 mg before 1 hour before lunch and 5 mg 1 hour before dinner OR 5 mg 1 hour before lunch and 5 mg 1 hour before dinner) when adverse effects are absent/minimal or when further therapeutic effect is desired
Maximum dose: 20 mg/day (10 mg orally 2 times a day

Hypersensitivity to dronabinol, sesame oil (capsules), alcohol (oral solution) or any component of the formulation; receiving, or have recently received, disulfiram- or metronidazole-containing products within 14 days (oral solution)

Frequency not always defined
>10%
 Central nervous system: Euphoria
1%
 to 10%
Cardiovascular: Facial flushing, palpitations, tachycardia, vasodilation, flushing, hypotension
Central nervous system: Abnormality in thinking, dizziness, drowsiness, paranoia, amnesia, anxiety, ataxia, confusion, depersonalization, hallucination, nervousness, chills, depression, headache, malaise, nightmares, speech disturbance
Dermatologic: Diaphoresis
Gastrointestinal: Abdominal pain, nausea, vomiting, anorexia, diarrhea, fecal incontinence
Hepatic: Increased liver enzymes
Neuromuscular & skeletal: Weakness, myalgia
Ophthalmic: Conjunctival injection, conjunctivitis, visual disturbance
Otic: Tinnitus
Respiratory: Cough, rhinitis, sinusitis
<1%
, postmarketing, and/or case reports: Burning sensation of skin, delirium, disorientation, exacerbation of depression, falling, fatigue, insomnia, loss of consciousness, mental status changes (exacerbation of mania or schizophrenia), movement disorder, oral lesion, panic attack, pharyngeal edema, seizure, skin rash, swelling of lips, syncope, urticaria, visual disturbance

Alcohol (Ethyl), Amphotericin B, Anticholinergic Agents, CNS Depressants, Cocaine (Topical),
CycloSPORINE (Systemic), CYP2C9 Inhibitors (Moderate), CYP3A4 Inducers (Strong),
CYP3A4 Inhibitors (Moderate), CYP3A4 Inhibitors (Strong), Disulfiram, Lumacaftor and Ivacaftor, Methotrimeprazine, MetroNIDAZOLE (Systemic), Ritonavir, Sympathomimetics,
Warfarin

You should not take dronabinol capsules if you are allergic to sesame oil

Dronabinol oral solution (liquid medicine) contains alcohol. You should not take dronabinol liquid if you have ever had an allergic reaction to alcohol or if you also use disulfiram (Antabuse) or metronidazole (Flagyl). Do not take dronabinol liquid within 14 days after or 7 days before using disulfiram or metronidazole

Women with HIV or AIDS should not breast feed a baby. Even if your baby is born without HIV, the virus may be passed to the baby in your breast milk

Dronabinol is not approved for use by anyone younger than 18 years old

Dronabinol may be habit-forming. Misuse can cause addiction, overdose, or death. Keep the medication in a place where others cannot get to it. Selling or giving away this medicine is against the law

Do not use marijuana while taking dronabinol

Avoid driving or operating machinery until you know how dronabinol will affect you. Dizziness or severe drowsiness can cause falls or other accidents

Do not drink alcohol while taking dronabinol

Safety and efficacy have not been established in pediatric patients; this drug is not recommended for use in these patients

Dronabinol may cause new or worsening psychosis (unusual thoughts or behavior), especially if you have ever had depression or mental illness

You should not use dronabinol capsules if you are allergic to sesame oil. You should not use dronabinol oral solution if you have had an allergic reaction to alcohol or if you also use disulfiram (Antabuse) or metronidazole (Flagyl

Dronabinol can raise or lower blood pressure, especially in older adults or in people with heart problems

Call your doctor at once if you have new or worsening mood symptoms, changes in behavior, headaches, vision problems, rapid heartbeats, or severe dizziness

Tell your doctor if you have ever had:
an allergy to any medication
epilepsy or other seizure disorder
heart problems, high or low blood pressure, fainting spells, fast heartbeats
alcoholism or drug addiction
depression, mental illness, or psychosis

To stimulate appetite in people with AIDS, dronabinol is usually taken 1 hour before lunch and 1 hour before dinner

To prevent nausea and vomiting caused by chemotherapy:
Take your first dose on an empty stomach, at least 30 minutes before eating.
After your first dose, you may take dronabinol with or without food but take it the same way each time.
Dronabinol is usually given 1 to 3 hours before your chemotherapy treatment, and then every 2 to 4 hours (up to 6 doses per day

Swallow the capsule whole and do not crush, chew, break, or open it

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon

Take the liquid medicine with a full glass of water

Do not stop using dronabinol suddenly after long-term use, or you could have unpleasant withdrawal symptoms. Ask your doctor how to safely stop using this medicine

Store the capsules or unopened liquid medicine in a tightly-closed container in the refrigerator. Do not freeze

You may also store the capsules at cool room temperature, away from moisture and heat. After opening the liquid medicine, store it at room temperature. Throw away any unused liquid 28 days after opening the bottle

Overdose symptoms may include changes in mood, memory problems, little or no urinating, constipation, loss of energy, problems with speech or coordination, or feeling light-headed

May cause fetal harm; avoid use during pregnancy