My lips are dry, itchy, crusting. using aquaphor lip balm regularly to avoid dryness of lips. visited a doctor who prescribed desonide gel 0.05% w/w and some b12 tablets. after applying gel, my lips are dry. can i apply aquaphor on top of gel?

Yes, you can. There is no reason why you should have any problem with the Aquaphor on top of the gel. Hopefully it will help, but if not, please contact your doctor again. It also would be important, if the desonide helps, to continue with the Aquaphor preventatively even after stopping the desonide and even if your lips seem better.

Might just be a good idea to leave the Lips alone for while, say 6 weeks to recoup from all the artificial applications. Simple soap and water used for normal Face Wash should be adequate. Vitamin C, E & B-complex supplement by mouth and application of Olive Oil at bed time if needed should help restore lips to their normal tone and consistency