Upon general principles; there are no special remedies.
How do external remedies act?
Mainly by removing the rete cells and with them the pigmentation; and partly, also, by stimulating the absorbents.
Are all external remedies which tend to remove the upper layers of the skin equally useful for this purpose?
No; on the contrary some such applications are followed by an increase in the pigment deposit.
Name the several applications commonly employed.
Corrosive sublimate in solution, in the strength of one to four grains to the ounce of alcohol and water; a lotion made up as follows:—
℞ Hydrargyri chlorid. corros., ..................... gr. iij-viij
Ac. acet. dilut., ............................... fʒij
Sodii borat., .................................... ℈ij
Aquæ rosæ, ...................................... f℥iv. M.
And also the following:—
℞ Hydrargyri chlorid. corros., ..................... gr. iij-viij
Zinci sulphat.,
Plumbi acetat., ..................āā.............. ʒss
Aquæ, ........................................... f℥iv. M.