Oral antihistamine

What is the best allergy treatment for eyes I mean the best eye drops for allergy. Not over-the-counter drugs. Oral antihistamine alone not helping.

I don't get any relief from fluticasone sprays in post nasal drip (oral antihistamines work) which means I am steroid non responder. Does it also mean I will be non responsive to oral steroids like prednisolone if ever taken for any medicalcondition?

Had septoplasty/turbinectomy to clear stuffy nose. Still producing clear mucus/stuffy feeling. No allergies & oral antihistamines not effective. Ideas?

Had allergic reaction to supp 6 weeks ago redness, itchiness, all over body. I have taken Cortisone and Antihistamines oral and injectable forms. I have since stopped cortisone, only using Dazit, Phenergan, and Fexo Antihistamines. Redness persists?

Does pollen season make oral allergy syndrome worse despite taking antihistamines?

Can you take a monteleukast with a 2nd gen antihistamine, and nasal corticosteroid? Would you be able to add an additional oral decongestant like psudoephedrine to this if decongestion is a concern? Is there a risk of rebound congestion?

What are the risks of low-dose oral prednisone taken over 1 or 2 decades? I am a vet with allergies to pets. Antihistamines not effective anymore.

Need to discontinue antihistamines r/t starting Pitolisant. Hx. of chronic hives and itchy skin. Hives havent been a problem recently but itchy skin has despite all topicals. Other oral meds for itchy skin? Ive taken doxepin in the past.

Is it bad to take an antihistamine during a cold, i.e. does suppressing mucus make the cold last longer?

What is the best OTC antihistamine?

Is antihistamine harmful to the body?

When should you take an antihistamine?

Is there an herb which can be used as an antihistamine?

Is Flixonase an antihistamine?

Is there an antihistamine cream?

Does antihistamine make you drowsy?

Can you use antihistamine and wine?

Is it ok to take antihistamines with ?

Can you take antihistamine with codeine?

Does an antihistamine help IC? If so how?