Sun Exposure During Active Rapamycin Dosing

I am interested what those who have long term experience with rapamycin think about limiting sun exposure during peak blood levels. I’m new to rapamycin and currently taking 5-6 mg. on alternate weeks. Most days, I spend time in the Arizona sun. Would it be a reasonable precaution to limit sun exposure for a few days during the rapamycin dosing cycle?


I would be sure to be extra conscious about covering up and using sun screen in the days immediately following dosing. The warning for sirolimus says:

This medicine may make your skin more sensitive to sunlight and can increase your risk of having skin cancer. Use a sunscreen when you are outdoors and avoid sunlamps and tanning beds

Source: Sirolimus (Oral Route) Side Effects - Mayo Clinic.

I put on sunscreen every day as a matter of habit, so I haven’t had to change my morning routine at all with rapamycin.


A guess, I suppose, but how many days after a single dose of 5 mg. would you say heightened skin vulnerability remains above average?

Second this, would love to know if avoiding sunlight altogether (on or around dosing day) - even with sunscreen - would be advisable? I live at altitude too, so those UVs are extra strong. Thanks!


Interesting, thanks for sharing that. I may need to get a higher SPF sunblocker when I cycle then.

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