I am currently taking the medication Effexor, and was wondering if it was okay to take Tylenol and Mucinex together
I don't know if these medications interact with one another, so I'd recommend that you call your pharmacist to make sure.
Your pharmacist is an often overlooked member of your health team
The information that I found online suggests that you should be fine taking them together, but it's far better to ask a professional than to rely on advice you get from a non-professional, particularly when it comes to drug interactions. It's a serious affair to mix medications, as you can see more clearly in this article.
This post on how to safely take Tylenol may also help you make a decision.