Hi, NyQuil contains 4 drugs
1.
Acetaminophen is a pain reliever and fever reducer.
2.
Doxylamine is an antihistamine that reduces the effects of the natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.
3.
Dextromethorphan is a cough suppressant. It affects the cough reflex in the brain that triggers coughing.
4.
Pseudoephedrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause
nasal congestion (stuffy nose).
side effects may be- allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
And It is not safe in pregnancy because of ALCOHOL and DEXTROMETHORPHAN which may cause fetal abnormality.
Many cold, flu, cough, fever or pain medications don't contain alcohol, DXM or aspirin, and these are deemed to be safe for pregnant woman. Try to use them.