Mixing LSD (acid) and NyQuil
Caution
Carries risk that is worth understanding before combining. Reduce doses and do not use alone.
Can you take LSD with NyQuil?
NyQuil contains acetaminophen, DXM and doxylamine. The most concerning part is LSD with NyQuil (Doxylamine): beyond an ordinary 25–50 mg dose of diphenhydramine, LSD makes its delirium worse and adds heart strain. Keep diphenhydramine to that dose. The doxylamine in NyQuil is checked as diphenhydramine (Benadryl), the closest drug MixSafe has data for, so this answer and any dose in it are diphenhydramine's. MixSafe rates LSD with NyQuil as "Caution" — carries risk that is worth understanding before combining. Reduce doses and do not use alone. Sources: the Drug Facts labels on DailyMed, the TripSit combination chart and MixSafe research. Educational information, not medical advice.
What is in it
- NyQuil
- Acetaminophen + DXM + Doxylamine. Doxylamine is checked as diphenhydramine (Benadryl): both are sedating antihistamines of the same kind. NyQuil Severe also contains phenylephrine, a decongestant MixSafe has no data for.
Ingredient by ingredient
LSD + NyQuil (Doxylamine)Caution
The doxylamine in NyQuil is checked as diphenhydramine (Benadryl), the closest drug MixSafe has data for, so this answer and any dose in it are diphenhydramine's.
Beyond an ordinary 25–50 mg dose of diphenhydramine, LSD makes its delirium worse and adds heart strain. Keep diphenhydramine to that dose.
At 25-50mg, DPH may assist with side effects of the LSD such as nausea and anxiety. At higher dosages, the combination of a deliriant (DPH) and LSD is cautioned against. LSD is likely to increase the deliriant and negative effects of DPH, in addition to increasing the risk of severe injury and mental trauma. LSD and DPH at recreational dosages have additional cardiac concerns such as vasoconstriction, tachycardia, hypertension, which in combination may be exacerbated.
Source: TripSit drug combination chart
LSD + NyQuil (DXM)Low risk, increased effect
Low risk of harm, but the effects amplify each other. Doses that are fine alone can be far too much together.
Low risk of harm, but the effects amplify each other. Doses that are fine alone can be far too much together.
Source: TripSit drug combination chart
LSD + NyQuil (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
- Vicks NyQuil Cold & Flu LiquiCaps, Drug Facts label. DailyMed, December 2025. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=efe4e649-7514-32dd-e053-2995a90a0492
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.
Think this is wrong, or know a better source? Send it.
Checking more than two?
The checker reads every ingredient in every box at once, and flags anything you would be taking twice.
Open this in the checker