Since fexofenadine and montelukast aren't providing enough relief, your elevated IgE levels suggest an underlying allergic trigger that needs a closer look. I recommend discussing a referral to an allergist or an ear, nose, and throat (ENT) specialist. They can evaluate you for conditions like cough-variant asthma and may recommend targeted therapies, allergy shots, or a sinus CT scan. In the meantime, using a daily saline nasal rinse and asking your doctor about a generic corticosteroid nasal spray may help soothe your airway.

Chronic nasal congestion often leads to mouth breathing, which can cause saliva to pool and look like frothing at night. The nasal redness is likely from rubbing. The abdominal pain could be a mild reaction to Allegra (fexofenadine) or Sinarest, particularly if taken without enough food, or from swallowing excess mucus. Please keep him hydrated and comfortable. I highly recommend visiting his pediatrician to safely investigate these symptoms and review his medicines.

For the most effective relief, it is generally best to use both the prescribed nasal spray and your Allegra (fexofenadine) tablets together as originally directed. While fexofenadine helps quickly with sneezing and runny nose, the nasal spray works over time to reduce deep inflammation and congestion, but it requires consistent daily use to be fully effective. Resuming both medications for the full month should help you feel much better. Please consult your doctor to ensure this combined approach remains the best fit for your specific symptoms.

Since your symptoms resolve with fasting but return when you stop antihistamines like hydroxyzine, levocetirizine, or fexofenadine, we should consider conditions like chronic spontaneous urticaria, a specific food allergy, or histamine intolerance. I reassure you that we can manage this. I highly recommend keeping a detailed food and symptom diary and consulting an allergist or immunologist. They can safely guide you through a supervised elimination diet and help you find a long-term management plan so you don't have to rely solely on daily antihistamines.

To help ease the pressure in your ears, a warm compress and nasal saline sprays can be very helpful. For the sore throat, warm saltwater gargles and staying well-hydrated work wonders. Over-the-counter pain relievers like paracetamol or ibuprofen can reduce discomfort. Since these symptoms are recurrent, it is highly recommended to see a healthcare professional. They can check for underlying causes like allergies or a sinus infection and guide you toward a lasting solution.

Since your symptoms return quickly after stopping deflazacort and fexofenadine, it is important to find a safer, long-term solution. Prolonged steroid use can have side effects. Under a specialist's guidance, next steps often involve increasing your daily non-drowsy antihistamine (like fexofenadine) up to four times the standard dose. If this is still ineffective, advanced therapies such as a targeted biologic injection (omalizumab) or other immunomodulating medications can be highly effective. Please consult an allergist or dermatologist to safely transition off the steroid and find a personalized treatment plan.