Another possibility is to take clenbuterol on a 2 day on 2 day off cycle. We definitely do not suggest this cycle for the simple fact that it does not give your body enough time to recover and get back to it’s normal state. Clenbuterol has an active half life of about 36 hours. In other words, when you take a single dose of clenbuterol, it remains active for at least 36 hour. Taking a 48 hour break obviously does not give the user enough time and if used long-term in this was, could actually be harmful to the user.