Table 1 Psychoactive substances used by study participants.

From: Acute induction of anxiety in humans by delta-9-tetrahydrocannabinol related to amygdalar cannabinoid-1 (CB1) receptors

Lifetime Illicit drug use

Cannabis

<5 times: 2 subjects;

5–20 times: 11 subjects;

25 times: 1 subject

Amphetamines

No use

LSD/Psilocybin

4 subjects ‡ (all had experimented a few times)

Cocaine

No use

Opiate

1 subject (experimented a few times)

MDMA

4 subjects (all of them had experimented a few times)

Other psychoactive substances (current use)

Nicotine

5 subjects ever smoked cigarettes;

Mean number of cigarettes smoked/day- 0.46 (SD-0.69) (range 0–2/day);

Caffeine

13 subjects;

Mean number of cups of coffee, tea or caffeinated drinks/day- 1.77 (SD-1.32) (range 0–4)

  1. ‡ 1 subject had experimented with both opiates & Psilocybin.