Hello. Thanks for writing to us at healthcaremagic
Sunscreen is an essential part of treatment of any facial
hyperpigmentation.
A sunscreen should be broad spectrum to be effective i.e should protect againt both UV B as well as UV A part of the spectrum
A sunscreen with a minimum spf of 30 or more is usually considered to be broad spectrum.
You should reapply it in adequate quantity (approx 3 ml or 1/2 a teaspoon for face and neck), every 2-3 hours.
The cream which has been suggested by you
dermatologist is a gold standard for treatment for facial pigmentation. It is a combination of
hydroquinone,
tretinoin and
mometasone.
The mechanism of action of these ingredients is inhibition of synthesis of new melanin and exfoliation of pre-existing melanin.
This cream can cause skin irritation and on long term use it can cause side effects like acne, sun-sensitivity etc
The duration of treatment with this cream should not exceed more than 6 weeks in any case.
Therefore, this cream should always be used under the supervision of a dermatologist and never over the whole face. It should just be used once daily at night, only over the dark spots.
Regards