noun
ointment; lotion; topical medicine
Refers to medicine applied directly to the skin, such as creams, ointments, or liniments.
虫刺されに付け薬を塗った。
I applied ointment to the insect bite.
この付け薬はかゆみに効く。
This lotion works for itching.
Compound of 付け (tsuke, 'attaching' or 'applying') + 薬 (kusuri, 'medicine'). The reading ぐすり is a rendaku form of くすり.