Dream suppression
Dream suppression can be described as a suppression of the vividness, intensity, frequency, and recollection of one's dreams. At its lower levels, this can be a partial suppression which results in one having dreams of a lesser intensity and a lower rate of frequency. However, at its higher levels, this can be a complete suppression which results in one not experiencing any dreams at all.
In the context of psychoactive substance usage, this effect can occur when certain compounds are ingested before a person sleeps. It is most commonly experienced under the influence of cannabis and other cannabinoids. This is due to the way in which they suppress REM sleep, the phase of sleep in which most dreams occur.
Psychoactive substances
Compounds within our psychoactive substance index which may cause this effect include: