Hello and welcome to healthcaremagic
I have gone through your concern and I have understood it.
UV A part of the electromagnetic spectrum is mainly responsible for tanning
Therefore, a good sunscreen should have broad spectrum UV A coverage in addition to UV B coverage, in order to be able to prevent tanning and it needs to be applied in sufficient quantity and every 2-3 hourly.
A sunscreen with minimum 30 spf would be adequate. It should mention both UV B and UV A coverage. Therefore it is important to select the right sunscreen for desired effects
It should be applied in the following quantity:
--3ml for face and neck(a little more than 1/2 teaspoon)
--3ml for each arm(a little more than 1/2 teaspoon).
A sunscreen should be applied every 2-3 hours. A sunscreen would prevent further tanning.
In addition to the sunscreens, you also need to use a demelanising cream to fade away the tan. If I was your treating doctor I would have asked you to use a cream containing one or more of the skin lightening agents e.g kojic acid
, glycolic acid
, arbutin or hydroquinone
etc once daily at night to gradually fade away the tan.
I hope you will find this information useful.