How long does humira stay in your system?

The half life is 2 weeks so it would be in your body for 10 weeks.

Taken from Marvell's answer here: https://www.drugs.com/answers/humira-how-long-does-humera-stay-in-the-body-once-476937.html

It takes 5.5. x elimination half life(hours or days, etc.) for a medicine to be cleared from ones system.

The elimination half life of Humira is between 10 to 20 days. If we use the maximum elimination half life then it would take approximately 110 days i.e more than 3 months (5.5 x 20 days) for it to be cleared from your system.