Skin Lighteners Flashcards
1
Q
Causes of hyperpigmentation
A
- skin diseases and conditions: melasma, etc.
- exogenous causes: cosmtics, drugs, photosensitivity
- other causes: addison disease, liver disease, pregnancy
2
Q
Action of hydroquinone
A
-inhibits the conversion of tyrosine to melanin. -melanocyte cytotoxic.
3
Q
Action of arbutin
A
inhibits melanosomal tyrosinase activity
4
Q
Action of kojic acid
A
tyrosinase inhibitor derived from fungi species
5
Q
Action of mequinol
A
substrate to the enzyme tyrosinase and acts as a competitive inhibitor of melanogenesis
6
Q
Action of vitamin C
A
interferes with pigment production by interacting with copper ions at the tyrosinase activity site and reducing dopaquinone
7
Q
Action of thiodiproprionic acid
A
antioxidant
8
Q
Action of azelaic acid
A
antiproliferative and cytotoxic effect on melanocytes
9
Q
Action of aloesin
A
acts as a competitive inhibitor of dopa oxidation and as a noncompetitor on tyrosine hydroxylase activity
10
Q
Action of retinoids
A
- derived from vitamin a
- inhibits tyrosinase induction
- may also interfere with pigment transfer to keratinocytes and accelerate pigment loss by causing the epidermis to be shed more quickly
