It is common for any part of your body that is exposed to direct sunlight to eventually darken over time. Yes, hydroquinone can lighten dark feet and it works the same way with the rest of the skin on your body.
Hydroquinone can be applied to the feet after they have been exfoliated and this will allow the cream to penetrate deeper. The skin on the feet will be thicker than the skin on your face so it will take longer to see results.
Now, if you continue to expose your feet to the sun, they will continue to darken even if you are using hydroquinone cream. It is important to wear shoes that protect your feet from the sun instead of sandals while you are treating them.
It may take 2-3 months before you see skin lightening results on the feet but this also depends on whether you are continuing to expose your feet to the sun.
Let the hydroquinone dry completely before you put on socks or shoes so that the cream does not come off. Another option is to use hydroquinone cream only at night and let it dry before going to bed.
Hydroquinone is the gold standard for skin lightening but you may also choose to use natural skin lighteners such as alpha arbutin or kojic acid on the feet.
Natural skin lighteners can be used year round and do not causes sun sensitivity, but we still recommend avoiding sun exposure during treatment.
There is a chance that the skin on your feet will darken again if exposed to sunlight. Hydroquinone does not permanently remove melanin producing cells so if you are out in the sun with sandals, your body will produce melanin.
Melanin is produced in the skin as a protective measure against UVA and UVB rays. The less you expose your skin, the lower your chances of skin darkening. Another great thing about protecting your skin from the sun is that it will keep your skin looking youthful.
If you experience skin darkening after your initial treatment with hydroquinone, you may restart treatment again. Allow 2-3 months for skin lightening and use sunscreen or sunblock on your feet and reduce the amount of time outdoors.