> Is there a drug (or other treatment) which can
> cause the patient's skin to produce more UV-resistant
> pigment?
Exposure to sunlight does this, by stimulating the production of
melanin. It is best undertaken in small doses.
Some fair-skinned people produce hardly any melanin at all. Exposure to
sunlight will only cause burns in these people.
Production of melanin can be stimulating by a pituitary hormone, MSH. I
don't know if there are drugs available that contain this hormone, or
how effective it is at production skin pigmentation in practical terms.
> On the same topic, what skin pigments are needed to
> block dangerous UV - is it just melanin or are there others?
Melanin does it
> I don't want skin cancer but at the same time I find
> sun lotion uncomfortable.
If you stay out of the sun, you should be okay. If you are living in
the UK, there isn't that much sunlight to begin with. You'll receive
far less sunlight in Western Europe than you would receive in the
American Southwest or Australia.
> Just taking a pill to darken my skin sounds the ideal
> solution to me, but does such a pill exist?
A quick look around reveals that some MSH products exist, but apparently
they are administered subcutaneously, not orally. It seems to me that
it would be more efficient to stimulate the pituitary to produce more
MSH itself, but I don't know if a way exists to do that.

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