From the Medscape website via the My Account section, select Professional Contact Information. 
 
Here you will be able to make changes to your profile information.   
 
Once you have made your changes, click the Update button at the bottom of the page.  
 
You will then be sent to an account management page and will see the message, "You've successfully updated your profile!"
 
If you do not see this message, look on the left side of the page for red text, indicating any error(s) or missing data.
 
After correcting the items in red, click Update. Your profile information will be updated.

*Changes to a Medscape profile must performed via our website; changes can not be accepted from the Medscape App.