I have bad seasonal allergies, zyrtec and clartin arent working. Can I take Benadryl (diphenhydramine) with the zyrtec?

OTC allergy meds. Combining Benadryl (diphenhydramine) and zyrtec may make you very drowsy so take it at night. You may like to try fexofenadine or Allegra instead; it's also non-sedating and can be taken once a day. Zyrtec and Claritin have derivatives that can be obtained only by prescription from your doctor. There are also nasal sprays that your doctor may try on you.