I make about $6,500 donating plasma over 100 times a year, but I don't do it for the money

• Patrick Herdener donates plasma twice a week, every week and makes between $50-$70 per donation.
• That means he typically donates plasma 104 times a year and makes about $6,500 before taxes.
• Herdener said he started donating for money but the spirit of being helpful motivates him now.

This as-told-to essay is based on a conversation with Patrick Herdener, who lives in Tulsa, Oklahoma, and donates plasma twice a week. He receives between $50-$70 per donation, which Insider verified with documentation. The conversation has been edited for length and clarity.

To be honest, when I first started donating plasma, the main thing that motivated me was money. I was in my mid-20s, unemployed, and had rent to pay.