Any safe effective solution to itching from minoxidil/finasteride compound (from pharmacy, by Rx)?

Many DHT-blocking shampoos have Ketoconazole as their active ingredient, which can result in itching an irritation to the scalp. You might be better off trying a different product (with the same DHT blocking intention) to see whether your scalp reacts better with that. I strongly suggest seeking thorough consultation with Trichoscopy scalp examination, to determine what exactly is causing your itching.Best, Dr. Anil Shah

itching is likely the DHT blocking shampoo (if it contains ketoconazole).  There are a couple of peptides that help heal hair follicles and promote hair growth (one of which blocks the DHT receptor on your scalp).  A LaserCap would improve your overall results.

Ideally, one needs to figure out the cause of the itching. And to do that, ideally one need to see the scalp up close. The most likely causes here are worsneing seborrheic dermatitis together with an irritant dermatitis from compounding agents. You might find it helpful to add an anti-dandruff shampoo to your routine and shampoo daily or every other day for a bit. Your dermatologist can add a mild cortisone (betamethasone valerate lotion) to help get you over this period. All in all see a dermatologist if it does not improved. There are a few common causes but practically speaking there are over 100 reasons for what you just described.