Ang itchy throat with cough and sipon ay usually viral, kaya mahirap talaga, one of my mum friends swears by honey (special honey from health stores, hindi yung regular), paracetamol for the discomfort, at plenty of warm liquids like chamomile or ginger tea. But honestly, if it's been a few days or if it's getting worse, mas better to check with your doctor agad kasi sometimes kailangan ng prescription to ease it properly, lalo na if may ubo na. How long na siya nag-persist?