Answer
Tretinoin absorption through the skin from Treclin gel was minimal in a study of 12 subjects with moderate to severe acne applying approximately 4 g daily for 14 days; plasma levels were below 1 ng/mL in 50–92% of subjects at any given time point and 1.0–1.6 ng/mL in the remainder.
Sources for this answer
- Treclin 1 %/0.025 % w/w GelViatris (formerly Mylan or Upjohn) · emc · SmPC §5.2 Pharmacokinetic properties · Version 7Document updated
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