Pharmacology of Hallucinogenics

Question 1

How long do bad LSD trips generally last?

Answer 1

24-48 hours

Question 2

What is the active ingredient of marijuana?

Answer 2

delta-9-THC

Question 3

True/False. A patient who previously used hallucinogens may experience flashbacks or memories from their last trip.

Answer 3

True

Question 4

What is generally a reliable sign of the end of a bad LSD trip?

Answer 4

A full night of sleep

Question 5

What physiologic effects does LSD have?

Answer 5

Sympathomimetic effects, illusions, pseudohallucinations, synesthesia (mixing of sensory information), emotionally labile

Question 6

A 50yo man uses marijuana for the first time with his college-aged son. The man experiences a rapid heartbeat, hyperventilation, and sweating. He presents to the ED with concern of a heart attack. What is the most likely cause of the patient’s presentation.

Answer 6

The man is likely suffering from a panic reaction due to marijuana use. This is generally due to freight during onset of physiologic effects of the drug

Question 7

True/False. PCP can remain in the body for days to weeks.

Answer 7

True

Question 8

True/False. LSD can cause poor judgment and feelings of invincibility. This may lead to unintentional suicide.

Answer 8

True. For example, a patient may believe they can fly and jump from a building

Question 9

A patient has previously been diagnosed with schizophrenia that is managed with an antipsychotic. They ask their doctor about starting medical marijuana to manage accompanying anxiety. What is the best course of action?

Answer 9

The patient should not use marijuana. Marijuana can produce psychotic reactions, even in a patient currently taking antipsychotics. An alternative to managing anxiety should be identified.

Question 10

LSD can produce pseudohallucinations. How are these different from hallucinations in psychotic disorders?

Answer 10

With pseudohallucinations, the patient does not believe the hallucinations are real. They understand they are due to intoxication and will resolve.

Question 11

What are the physiologic effects of marijuana?

Answer 11

Sympathomimetic effects, increased appetite, relaxation, euphoria, reduced psychomotor capacity

Question 12

What acute ADRs are associated with LSD?

Answer 12

Loss of control, panic, fright, and paranoia - most common in patients who have never used the drug previously

Question 13

What is the MOA of phenylcyclidine?

Answer 13

PCP - NMDA antagonist

Question 14

This treatment is recommended for LSD and related drugs, but should never be used with a patient using PCP.

Answer 14

Support and verbal contact. In a patient on PCP, this could cause agitation.

Question 15

What is the MOA of hallucinogenic drugs to induce hallucinations?

Answer 15

Agonists of 5-HT2 receptors that inhibit processes in the prefrontal cortex

Question 16

What is the last-resort treatment for a bad LSD trip?

Answer 16

Phenothiazine (typical antipsychotic), benzodiazepine

Question 17

What is the likely cause of death due to PCP toxicity?

Answer 17

Cerebral vascular attack due to hypertension

Question 18

PCP can exacerbate symptoms in a patient with this condition.

Answer 18

Psychosis in a patient with a psychotic disorder

Question 19

What symptoms are associated with chronic toxicity of marijuana?

Answer 19

Hyperemesis syndrome (recurring severe vomiting), bronchial irritation, reproductive abnormalities, reduced short term memory

Question 20

The effects of phencyclidine are similar to what analgesic drug?

Answer 20

Ketamine