Mixing Methamphetamine (meth) and NyQuil
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 Methamphetamine with NyQuil?
NyQuil contains acetaminophen, DXM and doxylamine. The most concerning part is Methamphetamine with NyQuil (DXM): both raise heart rate, and panic on this mix has led to serious heart problems. Avoid this combination. MixSafe rates Methamphetamine with NyQuil 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
- 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
Methamphetamine + NyQuil (DXM)Unsafe
Both raise heart rate, and panic on this mix has led to serious heart problems. Avoid this combination.
Both substances raise heart rate, in extreme cases, panic attacks caused by these drugs have led to more serious heart issues.
Class-level answer, inherited from Amphetamines. Nothing specific to this exact pair is documented, so treat it as the default for the class rather than a measurement of this drug.
Source: TripSit drug combination chart
Methamphetamine + 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.
Amphetamines can hide how confused diphenhydramine is making you, and together they strain the heart. Keep diphenhydramine to ordinary medical doses.
Amphetamines as a stimulant may mask some of the negative side effects of DPH, leading to delusions of sobriety which has additional concern in states of delirium. The combination of stimulants will increase strain on the heart and may cause some physical discomfort, and has the chance to cause life-threatening cardiovascular issues. The combination may also increase each other's neurotoxicity at higher dosages. The combination may increase anxiety levels and risks of thought loops on higher dosages, in addition to increasing each others negative side effects. Medical and common dosages of each substances are reported to not be a concern. Additionally, it is suggested that DPH potentiates amphetamine psychomotor activation, in addition to other interactions such as potentiation through inhibition of CYP2D6 and histamine H1 and H2 receptors, among other alterations.
Class-level answer, inherited from Amphetamines. Nothing specific to this exact pair is documented, so treat it as the default for the class rather than a measurement of this drug.
Source: TripSit drug combination chart
Methamphetamine + 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.
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