hepatotoxicity: chemical-driven liver damage or injury
Whilst the true (not anecdotal or case reports) effects on melasma are lacking via large studies there are some reports that it can help with melasma pigmentation, especially in combination with procedures such as lasers & novel chemical peels
Basically a study looked at 100 drugs & found that 90% of them were fully potent 15 years after their expiration date, though that may vary by drug, and perhaps liquid forms are a bit more vulnerable (perhaps)
Higher concentration means smaller volumes, which some people actually prefer
Ped Emerg Care, 24: 538-41 Kruithof PD, Lunev S, Aguilar Lozano SP, de Assis Batista F, Al-Dahmani ZM, Joles JA, Dolga AM, Groves MR, van Goor H
RUSSALD MEDICAL CENTER TIJUANA, MEXICO Where World-Class Medicine Meets Accessibility A multi-specialty medical center in Tijuana, minutes from San Diego