Can i combine nyquil and sudafed?

It Depends: Unfortunately, there are mult versions of Nyquil. Some contain the active ingredient in Sudafed (usually actually Sudafed PE which is phenylephrine). Other's do not. When it comes to OTC the counter meds it is as confusing and dangerous as if not more than prescriptions meds. Talk to your doc or pharmacist about the right product(s) for your specific needs and poss interaction with your presc meds