Substance
What not to mix with Caffeine
Stimulant
Also calledcoffee, energy drink, espresso, pre-workout, red bull, monster
Summary
Caffeine is checked against 40 other substances — 1 unsafe and 12 caution.
Unsafe
1Caution
12- Caffeine and AmphetaminesTwo stimulants strain the heart and can make you anxious and uncomfortable. Skip the caffeine, or keep it light.
- Caffeine and AMTCaffeine's anxiety is harder to manage while tripping, and together they can be physically uncomfortable. Keep caffeine light.
- Caffeine and CocaineTwo stimulants can race the heart and spike blood pressure. Keep caffeine light.
- Caffeine and DiphenhydramineCaffeine can hide how confused diphenhydramine is making you, and together they strain the heart. Keep diphenhydramine to ordinary medical doses.
- Caffeine and DOxCaffeine's anxiety is harder to manage while tripping, and together they can be physically uncomfortable. Keep caffeine light.
- Caffeine and DXMA lot of caffeine can make a dissociative trip more anxious and uncomfortable. Keep caffeine light.
- Caffeine and LithiumHeavy caffeine lowers lithium levels, and stopping suddenly can push them back up toward toxic. Keep your caffeine intake steady.
- Caffeine and MDMACaffeine adds little to MDMA and makes it more damaging to the brain. Skip the caffeine.
- Caffeine and MephedroneTwo stimulants strain the heart and can make you anxious and uncomfortable. Skip the caffeine, or keep it light.
- Caffeine and MethamphetamineTwo stimulants strain the heart and can make you anxious and uncomfortable. Skip the caffeine, or keep it light.
- Caffeine and NBOMesCaffeine brings out the stimulation in a psychedelic and makes the anxiety harder to handle. Keep caffeine light.
- Caffeine and PCPLittle is known about this pair, and PCP interacts unpredictably. Take less of each than usual, and do not use alone.
Low / synergy
1Low / decrease
1Low / no synergy
25Checking more than one?
This page rates Caffeine against one substance at a time. Combinations of three or more carry risks that no pair-by-pair list can show — the checker rates every pair at once and flags the whole-mix ones on top.
Open Caffeine in the checkerOther stimulants
All combinations →Educational information only, not medical advice. Absence of a documented interaction is not evidence of safety. Combination data from the TripSit drug combination chart, retrieved 2026-08-20.