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.

Since fexofenadine (Allegra) is no longer helping, you might try cetirizine or loratadine, which are effective, daily non-drowsy antihistamines. The skin darkening you are experiencing is likely post-inflammatory hyperpigmentation, a common and temporary response to skin inflammation and scratching that typically fades once the itching stops. To soothe your skin, cool compresses or a mild hydrocortisone cream can help. Consult a healthcare provider to safely adjust your treatment and ensure you find lasting relief.

It is generally safe to start swimming, but you need to take extra care of your skin. Sotret (isotretinoin) makes your skin dry, sensitive, and highly prone to sunburn, and pool chlorine can cause further irritation. Allegra (fexofenadine) is perfectly safe to continue. To protect yourself, apply a thick moisturizer before and after swimming, rinse off with clean water immediately after exiting the pool, and use a broad-spectrum, water-resistant sunscreen of SPF 50 or higher if you are swimming outdoors. If your skin rash worsens or becomes highly irritated, take a brief break and consult your doctor.

Allegra (fexofenadine) works by blocking histamines, which temporarily relieves your itchy eczema, but it does not cure the underlying cause. When you stop taking it, the symptoms return because the trigger is likely still present. Fexofenadine is generally safe for long-term daily use under a doctor's guidance. However, since the rash is on your upper lip, it could be a contact allergy to something like toothpaste, lip balm, or food. I highly recommend speaking with your doctor or a dermatologist to help identify the trigger and discuss targeted topical treatments for lasting relief.

Treatments like Allegra-M (fexofenadine and montelukast) and nasal sprays aren't helping. Since these symptoms have lasted this long, it might not be a simple allergy. It could be related to non-allergic rhinitis, nasal polyps, or a chronic sinus issue. I highly recommend consulting an Ear, Nose, and Throat (ENT) specialist. They can gently examine your nasal passages to find the exact cause and help you find a treatment that finally brings you comfort.

Frequent nose and throat infections during weather changes may be due to an allergy or low immunity. Allegra helps control allergy symptoms but may not prevent infections completely. Avoid cold exposure, maintain good hygiene, and support your immunity with a healthy lifestyle. Consult a doctor to review your condition and confirm the most suitable treatment.