Combination

Mixing Diphenhydramine and Ketamine

DeliriantDissociative
Diphenhydramine also called
benadryl, dph, sleep aid, zzzquil, unisom
Ketamine also called
ket, special k, kitty, kittens
Verdict

Dangerous

Both substances potentiate the ataxia and sedation caused by the other and can lead to unexpected loss of consciousness at high doses. While unconscious, vomit aspiration is a risk if not placed in the recovery position. Ketamine has a high likelihood of increasing DPH's deliriant effects at higher dosages and can greatly increase the risk of injury, mania, and psychosis. Medical dosages of both substances are unlikely to cause concern.

Risk / Physical + headspace

This combination carries bodily risk and can go badly psychologically. The headspace part often arrives first and makes the physical part harder to notice.

Can you mix Diphenhydramine and Ketamine?

High risk of death or life-changing injury. Do not combine.

Source

TripSit drug combination chart, retrieved 2026-08-20. View the dataset.

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Rated dangerous. Educational information only, not medical advice. Absence of a documented interaction is not evidence of safety.