If you are a non-member subscriber, yes. Your Pharmaceutical Journal website account is identified in the registered user database by a number, so if you go to My Account > My Account, you can change your surname, other details, your password and even the email address that you use to log in with.
You can enter separate information about yourself that other users can see, e.g. if you leave a comment on an article, at My Account > My Profile.
If you use the RPS member login route, however, only this "My Profile" biographical information for display to readers of your comment(s) is editable; no account data are accessible for viewing or editing.
If you upload a photograph of yourself to My Profile or give yourself a screen name, these will always displayed beside your comment, together with a link to the profile.