Mixing DXM (robo) and Tylenol PM
Unsafe
Risk of serious physical or psychological harm. Not recommended under any circumstances.
What to do
- Say what was taken and how much.Responders need it, and in most US states Good Samaritan laws protect both of you from drug possession charges when you call for an overdose.
- Unresponsive: put them on their side, tilt the head back, and stay until help arrives.Never leave someone alone to “sleep it off”.
- Never Use Alone 1-800-484-3731Stays on the line and sends help if you stop responding.
- Full steps: what to do if it is already happeningOverdose signs, the recovery position, what to say on the call, and whether you can be charged for making it.
- Poison Control 1-800-222-1222Free and 24/7, for “is this bad?” before it becomes an emergency.
Can you take DXM with Tylenol PM?
Tylenol PM contains acetaminophen and diphenhydramine. The most concerning part is DXM with Tylenol PM (Diphenhydramine): diphenhydramine raises DXM levels, and together they risk serotonin syndrome, delirium, overheating and heart strain. Avoid this combination at recreational doses. MixSafe rates DXM with Tylenol PM as "Unsafe" — risk of serious physical or psychological harm. Not recommended under any circumstances. Sources: the Drug Facts labels on DailyMed, the TripSit combination chart and MixSafe research. Educational information, not medical advice.
What is in it
- Tylenol PM
- Acetaminophen + Diphenhydramine.
Ingredient by ingredient
DXM + Tylenol PM (Diphenhydramine)Unsafe
Diphenhydramine raises DXM levels, and together they risk serotonin syndrome, delirium, overheating and heart strain. Avoid this combination at recreational doses.
The combination is reported to reduce the side effects of each drug and potentiate many of the recreational effects. There is a significant risk of serotonin syndrome, increased delirium, CNS depression, cognitive inhibition, risk of physical injury, hyperthermia, mania, paranoia, and psychosis, especially at higher dosages. There is an additional concern of tachycardia, hypertension, and in extreme cases, heart failure. Diphenhydramine is reported to inhibit the CYP2D6 enzyme which can increase levels of DXM. Medical dosages are not reported to be a concern. Caution is strongly recommended with this combination.
Source: TripSit drug combination chart
DXM + Tylenol PM (Acetaminophen)Low risk, no synergy
Neither substance is expected to meaningfully change the other. Both still carry their own individual risks.
No specific interaction is documented. Acetaminophen's main risk is dose-dependent liver injury, so the thing to watch in any combination is total daily intake across all products (roughly 4g/24h) and anything else straining the liver.
Sources: Prescott LF. Paracetamol, alcohol and the liver. Br J Clin Pharmacol. 2000 · Acetaminophen: A Liver Killer or Thriller
- Tylenol PM Extra Strength, Drug Facts label. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=ce58105b-f010-47af-8f31-6dd4ce4e9cba
Ingredient lists checked 2026-09-27. Formulas change and store brands differ, so the Drug Facts box on your own packet is the final word.
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