Review Question - QID 105614

The patient in the above vignette is experiencing hallucinations, xerostomia, and increased appetite in addition to exhibiting conjunctival injection and tachycardia, most likely due to marijuana abuse.

The psychoactive constituent of marijuana is delta-9-tetrahydro-cannabinol (THC), which exerts its effects by binding to the CB1/CB2 receptors. Intoxication can present with euphoria, anxiety, disinhibition, paranoid delusions, perception of slowed time, impaired judgment, social withdrawal, increased appetite, dry mouth, and hallucinations. Treatment is limited to symptom management. Withdrawal from marijuana typically causes mild irritability, depression, insomnia, and anorexia.

Hubbard et al. describe the acute effects of marijuana intoxication as well as the adverse effects of chronic abuse. The adverse effects of chronic marijuana abuse include decreased coordination, epithelial damage to the lungs, increased risk of infection, cardiovascular changes and cognitive deficits. The authors also note the occurrence of social withdrawal and poor performance in school or work.

Raphael et al. report that while cannabis has traditionally been seen as a somewhat harmless drug, it is commonly used as a gateway drug. Moreover, they provide support for a link between marijuana abuse and the development of psychosis in addition to other mental health disorders and social withdrawal. The authors support the use of public health programs to decrease cannabis abuse.

Illustration A depicts a clinical image of conjunctival injection.
Illustration B is an artist's rendering of the various physiological effects of cannabis.

Incorrect Answers:
Answer 1: Cocaine can cause paranoid ideations and tachycardia, but it is not known to cause conjunctival injection and it is an appetite suppressant.
Answer 2: Phencyclidine (PCP) can also cause hallucinations, paranoia, and tachycardia, but it is not known for conjunctival injection, xerostomia, or increased appetite.
Answer 3: Benzodiazepines are depressants and would present with psychomotor slowing, ataxia, and respiratory depression. They are not known to cause hallucinations are tachycardia.
Answer 5: Heroin is an opioid and acute intoxication would present with miosis rather than conjunctival injection and opioids frequently causes nausea rather than increased appetite.