SARMs begin to activate in the system within 48-72 hours. Considering most SARMs cycles take 8-12 weeks, that’s two to three months that SARMs will be in your system. In most cases, taking a PCT cycle for SARMs comes after this, so it’s fair to say SARMs remain in your system for at least three months after initial use.
Don’t take this as a criticism of SARMs. Supplements take time to work, so they’ll be in your system for a while, but that doesn’t mean they’re dangerous if you follow the guidelines.