Itching in underarms. Advise what to do.

You must be having fungal infection. Fungal infection tends to affect folds of the skin, moist areas like groins, armpits, mouth, genitals, under the breasts, webs between fingers and toes, etc. Our skin protects us from fungal/yeast attack, but any cut or break in the continuity of the skin can allow penetration of fungus. It gives rise to rash, eruptions, redness, burning, intolerable itching and abnormal discharges at times. Fungal infection tends to last for many years if not treated well. It is also contagious.Avoid steroid containing creams like Zole F etc.  application of steroid containing creams Betnovate etc just suppresses it on surface but it grows beneath the skin and spreads everywhere and also becomes more resistant

Consult on private chat with clinical photographs for personalised treatment

Following healthfeed should be helpful "Fungal Infection, Ringworm: What You Should Know" by Dr. Jolly Shah Kapadia - https://www.practo.com/healthfeed/fungal-infection-ringworm-what-you-should-know-14722/post "Top 10 Ways to Keep Fungal Infection at Bay !" by Dr. Jolly Shah Kapadia - https://www.practo.com/healthfeed/top-10-ways-to-keep-fungal-infection-at-bay-24925/post