Can I take NyQuil every night?

What is in NyQuil, and which part makes you sleepy?

Standard Vicks NyQuil Cold & Flu liquid has 3 active ingredients in each 30 mL dose. It treats cough, sore throat, headache, minor aches, fever, runny nose, and sneezing from a cold or flu.

The drowsiness comes from doxylamine, a sedating antihistamine. The label warns that marked drowsiness may occur. NyQuil Severe Cold & Flu adds a fourth ingredient, the decongestant phenylephrine, and has a slightly lower dextromethorphan dose. Always read the Drug Facts on your own bottle, since NyQuil comes in several versions.

• Acetaminophen 650 mg: pain reliever and fever reducer, the same drug as Tylenol.
• Dextromethorphan HBr 30 mg: cough suppressant (20 mg in Severe).
• Doxylamine succinate 12.5 mg: antihistamine, the part that makes you sleepy.
• Phenylephrine HCl 10 mg: nasal decongestant, in NyQuil Severe only.

How many nights in a row can you take NyQuil for a cold?

The label does not give a fixed number of nights. It gives stop points instead. Stop and ask a doctor if pain or cough gets worse or lasts more than 7 days, if fever gets worse or lasts more than 3 days, or if new symptoms, redness, or swelling appear. Also stop if a cough comes back or comes with a rash or a headache that won't go away.

So a few nights of NyQuil during a cold fits the label. Needing it night after night past a week is the label's own signal to get checked rather than keep going. The CDC also says to seek care if cold symptoms last more than 10 days without getting better.

If you take NyQuil Severe, the label adds that you should stop and ask a doctor if you become nervous, dizzy, or sleepless, or if nasal congestion lasts more than 7 days.

Is it OK to take NyQuil just to sleep?

It is not a good plan. NyQuil is a cold and flu medicine. If you take it only to sleep, you also swallow acetaminophen and a cough suppressant you don't need.

Doxylamine on its own is sold as a sleep aid, for example Unisom SleepTabs at 25 mg per tablet. Even that product's label says to stop and ask a doctor if sleeplessness lasts continuously for more than 2 weeks, because insomnia may be a symptom of a serious underlying illness. MedlinePlus says doxylamine should only be used for insomnia for a short time, and to call your doctor if you think you need it for more than 2 weeks.

Tolerance is another reason. MedlinePlus notes that most OTC sleeping pills contain antihistamines and that your body quickly becomes used to them. The NHS says pharmacy sleep aids may help for 1 to 2 weeks and cannot cure insomnia.

• Don't add a second sleep aid with doxylamine. The Unisom label says not to use it with any other doxylamine product, and NyQuil already contains it.
• Don't stack other antihistamines or sedatives without asking a doctor or pharmacist first.
• Age 65 or older: MedlinePlus says older adults usually should not take doxylamine, because other medicines are safer and more effective.

How much acetaminophen are you getting from nightly NyQuil?

One 30 mL dose of NyQuil Cold & Flu has 650 mg of acetaminophen. The label allows no more than 4 doses in 24 hours, which is 2,600 mg from NyQuil alone. One nightly dose is 650 mg, but it still counts toward your daily total from every product you take.

The bigger risk is doubling up. The NyQuil label says do not use it with any other drug containing acetaminophen. That includes Tylenol and many daytime cold, flu, and headache products, so check the Drug Facts of everything you take that day.

The label warns that severe liver damage may occur if you take more than 4 doses in 24 hours, take it with other acetaminophen products, or have 3 or more alcoholic drinks every day while using it. If you have liver disease, ask a doctor before you use it.

Who should check with a doctor before using NyQuil at all?

The labels list specific conditions and medicines that call for a doctor's or pharmacist's advice first. Pregnant or breastfeeding? Ask a health professional before use. Children under 4 should not use it, and children 4 to under 12 need a doctor's advice.

• Do not use if you take an MAOI (some antidepressants and Parkinson's medicines) or stopped one within the last 2 weeks.
• Ask a doctor first if you have liver disease, glaucoma, a breathing problem or chronic cough (such as from smoking, asthma, chronic bronchitis, or emphysema), a cough with a lot of phlegm, or trouble urinating from an enlarged prostate.
• NyQuil Severe (phenylephrine): ask a doctor first if you have high blood pressure, heart disease, thyroid disease, or diabetes.
• Ask a doctor or pharmacist first if you take sedatives, tranquilizers, or the blood thinner warfarin.
• Avoid alcohol and be careful driving or using machinery. Alcohol, sedatives, and tranquilizers can increase the drowsiness.

What should you do if you can't sleep without NyQuil?

Reaching for NyQuil after the cold is gone usually means the sleep problem is its own issue. The NHS says to see a GP if changing your sleep habits hasn't helped, if you've had trouble sleeping for months, or if it makes daily life hard to manage. Insomnia that lasts 3 months or more is called long-term insomnia.

The NHS says insomnia is sometimes treated with cognitive behavioral therapy (CBT), which helps you change the thoughts and behaviors that keep you from sleeping. It can be done face to face with a therapist or through an online self-help program. Our AI doctor can help you sort out whether the problem is a lingering cough, a sleep habit, or something that needs a clinician, and a clinician decides whether any prescription is right.