Chemsex is a growing concern among men who have sex with men (MSM). COVID-19 lockdowns have had consequences on social and sexual interactions. We aimed to assess changes in chemsex practices during COVID-19 lockdown in France among MSM and factors associated with maintaining or increasing chemsex practice.

Repeated face-to-face questionnaires were conducted at “Le 190” Sexual Health Center, Paris, France, exploring lifestyle, sexual, and chemsex practices, COVID-19 concerns and mental health before and during second lockdown in France (30/10/2020–15/12/2020). Inclusion criteria were chemsex practices at least 3 times throughout lifetime and at least once in the 3 months before second lockdown. The primary end point was the proportion of participants who declared having stopped, decreased, maintained, or increased their chemsex practice during lockdown. Univariable and multivariable logistic regressions were used to analyze factors associated with evolutions of chemsex practice.

Ninety-three MSM were included: 66% HIV-positive and 30% taking PrEP. Drugs most used were cathinones (91%) and GHB/GBL (52%). Participants reported stopping, decreasing, maintaining, and increasing chemsex drugs use in 14%, 22%, 22%, and 42% of cases, respectively. Despite this overall increase in chemsex practice, MSM decreased their number of sexual partners. Factors significantly associated with maintaining or increasing chemsex drugs use were feeling lonely (OR = 3.24), craving (OR = 4.51), and working during lockdown (OR = 3.27), contrasting with fear of COVID-19 (OR = 0.31).

Restriction measures lead to changes in sexual behavior and seem to increase chemsex practice. Maintaining care for most isolated patients should be a priority in COVID-19 context.