Feeling numb on the face after taking mucinex dm?

Never heard of that happening I suggest a different medicine with no side effects.

Make sure if he is still having numbness to call the doctor outside of that he should be okay and if he can drink extra water or if it is worse than yesterday call the doctor.

Smilehy012; If it has not gone away by now you should give the doctors office a call. And don't take anymore if he needs something go to the pharmacy and tell the Pharmacist what happened with this one and have them find something he can take Here is a list of side effects most common that you should check with a doctor.(((For the Consumer

Applies to dextromethorphan / guaifenesin: capsules, elixir, extended-release liquid, extended-release tablets, granule packets, liquid, solution, suspension, sustained-release tablets, syrup, tablets

Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Dizziness; drowsiness; stomach upset.

Seek medical attention right away if any of these SEVERE side effects occur while taking dextromethorphan / guaifenesin:
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue) Does not really mention anything your Husband is having but best not to take anymore.