Dronabinol adverse effects

In a randomized, double-blind, placebo-controlled, crossover trial the effect of the synthetic delta-9-tetrahy-drocannabinol dronabinol on central neuropathic pain was evaluated in 24 patients with multiple sclerosis (58). Oral dronabinol reduced central pain. Adverse events were reported by 96% of the patients compared with 46% during placebo treatment. They were more common during the first week of treatment. The most common adverse events during dronabinol treatment were dizziness (58%), tiredness (42%), headache (25%), myalgia (25%), and muscle weakness (13%). There was increased tolerance to the adverse effects over the course of treatment and with dosage adjustments. 

Thirty randomized, controlled trials from 1975 to 1996 were analyzed to quantify the antiemetic efficacy and adverse effects of cannabis when given to 1366 patients receiving chemotherapy. Oral nabUone, oral dronabinol, and intramuscular levonantradol were compared with conventional antiemetics (prochlorperazine, metoclopramide, chlor-promazine, thiethylperazine, haloperidol, domperidone, and aliza-pride) or placebo. Across all trials, cannabinoids were slightly more effective than active comparators and placebo when the chemotherapy regimen was of moderate emetogenic potential, and patients preferred them. No dose-response relationships were evident to the authors. The cannabinoids were also more toxic side effects included euphoria, drowsiness, sedation, somnolence, dysphoria, depression, hallucinations, and paranoia. The efficacy of cannabinoids as compared to SSRls has not been studied. Use of these agents should be considered when other regimens do not provide desired efficacy. 

ADVERSE EFFECTS Dronabinol has complex effects on the CNS, including a prominent central sympathomimetic activity that can lead to palpitations, tachycardia, vasodilation, hypotension, and conjunctival injection (bloodshot eyes). Patient supervision is necessary because marijuana-hke highs e.g., euphoria, somnolence, detachment, dizziness, anxiety, nervousness, panic, etc.) can occur, as can more disturbing effects such as paranoid reactions and thinking abnormalities. After abrupt withdrawal of dronabinol, an abstinence syndrome manifest by irritability, insomnia, and restlessness can occur. Because of its high affinity for plasma proteins, dronabinol can displace other plasma protein-bound drugs, whose doses may have to be adjusted as a consequence. Dronabinol should be prescribed with great caution to persons with a history of substance abuse because it also may be abused by these patients. 

There was no adverse effect on viral load or CD4 count in the patients receiving cannabis cigarettes or dronabinol. ... 

Chlorpromazine, prochlorperazine, promethazine, methylprednisolone, lorazepam, metoclopramide, dexamethasone, or dronabinol may be used for adult patients. Around the clock dosing should be considered. The choice of specific agent should based on patient specific factors, including potential for adverse drug reactions, and cost. SSRIs are effective for breakthrough nausea and vomiting but they are not superior to the less expensive antiemetics above. 

The cannabinoids act on the cerebral cortex and have the same side effects and adverse reactions as antihistamines and anticholinergic. These include drowsiness, dry mouth, blurred vision, tachycardia, and constipation. Caimabinoids include dronabinol and nabilone. These drugs should not be administered to glaucoma patients because they dilate the pupils (mydriasis). They are contraindicated for use in patients with psychiatric disorders and also used as an appetite stimulant for patients with AIDS. Side effects include mood changes, euphoria, drowsiness, dizziness, headaches, depersonalization, nightmares, confusion, incoordination, memoiy lapse, dry mouth, orthostatic hypotension, hypertension, and tachycardia. Less common symptoms include depression, anxiety, and manic psychosis. 

Key Words Cannabis marijuana dronabinol human smoked adverse events cardiovascular neurological cognition performance subjective effects. 

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