Would anyone (prferably a doctor or pharmacist) know how much NyQuil one would have to consume before an overdose?
I’m not a doctor or pharmacist, but a putting away an entire bottle at once might cause serious harm, if it didn’t kill you. Among other things, NyQuil contains acetaminophen, which is damaging to one’s liver in high doses. It’s hard to say, because every person is different. I know a person who once drank an entire bottle with no ill effects, yet, conversely, there are people that have died as a result.
I spent some time searching the net but couldn’t come up with any specific numbers. IIRC, it is possible to overdose on acetominophen by taking only a small multiple of the correct dose, possibly as little as twice the correct dose for some people. Also, IIRC, people get into trouble with acetominophen because it is contained in so many OTC products and people often take OTC products without knowing what is in them. For example, if someone took the maximum recommended dose of Tylenol for a headache and then took the maximum recommended dose of NyQuil to sleep they could approach a toxic level if they started out with a bad liver.
Nowadays, in well equipped hospitals, the treatment of acetominophen intoxication is based on measurement of acetominophen levels in individual patient, not on how much the patient said she ingested.
If your really want to know “how much NyQuil one would have to consume before an overdoseat” you could try asking either the Vicks people (who sell NyQuil) or a poison control center.
I am a doc, and the previous poster was correct, it’s the acetaminophen that is the consumption limiter. It will kill you long before the antihistamines, decongestants, alcohol, cough suppressant, corn syrup, propylene glycol, ethylene glycol, saccharine, glycerine, D&C yellow number 10 and FD&C blue number 1 coloring would. How much it would take to kill you depends on your size and condition. Less than 10 grams generally won’t kill an adult, but if you’ve been drinking (and nyquil has alcohol in it) all bets are off. For kids, doses of less than 150 mg/kg are generally not lethal, but then again, they could be.
Why not try a nice cup of tea and a hot shower?
Just an aside, but for those on SSRIs, it’s better not to use products with the cough suppressant dextromethorphan hydrobromide, like Nyquil.
No more Nyquil for me 
--all part of the medication tradeoff.
Eh? I hadn’t heard this one before. I shall have to check my PDR. (I’m on Prozac, and currently dealing with a nasty cough for which, at least at night, I’m taking a medication including dextromethorphan.)
It should be noted, of course, that dextromethorphan is only a good thing when you really need to stop coughing–like when you’re trying to sleep. At other times, dose up on guafenisen and hack away, hoping some of those germs will expedite themselves out of your lungs. (This was the suggestion of a doctor).
LL
Dextromethorphan, or DXM, has a few other problems associated with it too. It has a mild anti-cough action in low to medium doses, but acts as a dysphoric and hallucinogen in larger doses. In very high doses, its actions mimic PCP, a popular animal tranquilizer and psychosis inducer. It gets press regularly when the local high school kids discover chugging a bottle of robitussin DM (Robo, to those in the know) whacks them out.
Its effects really aren’t pleasant. The corn syrup base it comes in causes a large osmotic diarrhea, and when the drug kicks in, the user starts having gait and coordination problems, stumbling and bumping into things, and having difficulty navigating complex courses such as turning 90 degrees. Hallucinations often begin with a deja vu phenomenon, followed by presque vu, or almost seen, as images seem to just be beyond the edge of vision. The scalp may start tingling, and this may represent a pre-epileptic excitement phase. Full blown seizures have been known to follow.
Remember that basically your cough is there for a reason, to protect and clear your lungs. Use cough suppressants only for those coughs that prevent you from doing the basic acts of daily living. And avoid shotgun cold medicines designed to relieve multiple symptoms, many of which you probably won’t have all at once.
This lecture has been brought to you by the committee for responsible over the counter medication consumption.
I emailed Vicks - the following is my question followed by Barb’s response:
“How much NyQuil would one have to consume to overdose?”
Hi Craig.
We can only recommend using this product according to labeled directions.
Barb
USA Vicks Team
And there you have it from the legal perspective