How long can you use sarna sensitive lotion on glans and under penis no itching dry scarred senseituve skin lotion was given by dr. at u.p.m.c?

You can stop: if the initial period of itching has stopped, then ok to stop using lotion (1-2 weeks should be adequate). If skin remains dry, you could switch to "non-medicated" emollient such as Vanicream or Aquaphor, which would be less sensitizing. I hope I understood the question. Check with your UPMC doctor, they are highly respected

Not a steroid: Since Sarna Sensitive isn't a steroid, there's no hard & fast time limit for its use. As long as you have this problem, you can continue to use the Sarna Sensitive as directed. If the condition starts getting worse, however, you should discontinue the Sarna Sensitive and see your doctor again.