Brief Answer:
Likely to be an upper respiratory infection

Detailed Answer:
Hello and welcome,

I'm sorry you are not feeling well.

Xyzal is an antihistamine, so if you are having problems with allergies, this should cover it. Singulair also works on allergies too. So I don't think taking Benadryl, which is an antihistamine, would be helpful right now.

If your throat is sore and your glands are swollen, and you aren't having symptoms typical of allergies for you (such as itchy nose and eyes, etc), this is likely an upper respiratory infection that you are fighting. If your throat is quite bad (painful) and you feel feverish, chills, aches, it may be strep and for that I recommend going in to an urgent care clinic or your doctor's office (if you can get in tomorrow) for a throat swab.

If it is strep, then an antibiotic is needed.

If not, it is likely to be a viral infection and for that, suggestions are:
- nasal saline (if you have post nasal drainage causing the sore throat)
- oral decongestant (providing you don't have high blood pressure or other reasons not to take this)
- acetaminophen (Tylenol) for aches and pains
- hot wet compresses on the glands of your neck if it is comfortable for you
- plenty of fluids
- rest (very important)
- some people anecdotally find benefit from increase Vitamin C and zinc at the beginning of an infection

I hope this information helps. Please let me know if I can provide further information or clarification.

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