Which drug class is known to suppress REM sleep?

• A. Ramelteon
• B. SSRIs/SNRIs
• C. Melatonin
• D. Z-drugs

Answer: (B)

REM sleep is particularly vulnerable to the effects of monoaminergic antidepressants. SSRIs and SNRIs increase serotonin and norepinephrine activity, which dampens the brainstem circuits that generate REM sleep. Clinically, this shows up as a reduced amount of REM sleep and longer time to first REM—REM latency—and, over time, a lower REM density. That robust pattern makes SSRIs/SNRIs the drug class most consistently associated with REM sleep suppression.

Ramelteon and melatonin primarily help with initiating sleep and stabilizing the circadian rhythm by acting on melatonin receptors; they don’t reliably suppress REM sleep. Z-drugs mainly promote sleep initiation and maintenance with variable effects on sleep stages, but their impact on REM is not as pronounced or consistent as with SSRIs/SNRIs.