Yes, rashes around joints with itching can be a sign of an allergy. However, joint-area rashes can also occur with infections or skin conditions. Hence, it is best to see a doctor for proper diagnosis and treatment.

Small itchy patches on the neck after sun exposure are often due to sun rash, heat rash, or irritation. Try to avoid direct sun, keep the area cool and clean, wear loose cotton clothing, and apply a mild moisturizer or calamine lotion. If itching is bothersome, an antihistamine may help. See a doctor if it worsens, spreads, or does not improve in a few days.

Colour change with itching in the penis or testicles is most commonly due to a fungal infection, skin irritation, sweating, or contact allergy. Taking Xyzal helps with itching but does not treat the cause. Keep the area clean and dry and avoid tight clothing. See a doctor for proper treatment.

Xyzal is generally safe to take for a longer period if prescribed by the doctor. If you need it daily for many weeks, it is best to check with your doctor to find and treat the underlying cause of the allergy.

Sudden itching and redness spreading from the hands to the legs suggest an allergic reaction. Keep the skin cool, avoid scratching, and apply calamine or a mild moisturiser. See a doctor urgently if it keeps spreading, or if you have swelling of the lips/face or breathing difficulty.

Since your grandmother still has rashes and itching even a year after stopping the antidepressant, it is important to see a doctor or dermatologist. Persistent itching may have another cause that needs testing. A doctor can suggest safer treatments or check for other underlying issues.