Thirteen-year-old Danielle Lei set up her cookie stall outside of the clinic in San Francisco and was welcomed by patients and staff.

Danielle sold out of her first batch within 45 minutes, according to the clinic, which is a fully licensed dispensary serving qualified California patients.

The Green Cross wrote on Facebook: "When the Girl Scouts set-up shop outside The Green Store storefront yesterday, little did they know they'd need to call for back-up Girl Scout Cookies after 45 minutes!

"It's all about location and it's safe to say this one was a great success."