Is it useful to use starch with rosewater topically for acne ?

Get a real Rx: Acne is a serious, chronic disease that is often a grave personal and professional liability & needs to be managed scientifically. "pop" / "fun" remedies are appropriate only as an adjunct to the topical treatment that you are already receiving, a topical retinoic acid derivative. If this is not giving you the relief you need, your physician may add topical clincamycin or something else that works.

Acne: Why would you want to use this combination when retina will do a wonderful job. If your skin is getting to dry or ed, try using a moisyrizer.