1% of the population develops a skin allergic reaction to Andrographis that can be very severe. This is why Buhner no longer recommends it, he got lots of complaints from people.buhnerhealinglyme.com/herbs/andrographis-severe-skin-reaction/
HOWEVER, Andrographis is a very potent herb against Lyme disease, so i don't see a reason why people cannot test if they have a rash with a low dose and decide if they can use it or not.
I am currently getting herbal treatment from Germany and they use a herbal cocktail with Andrographis as main ingredient, along with Artemisinin, Grapefruit seed extract, Resveratrol (knotweed), Chorella, Allicin and many many others. They seem less concerned with the allergic reaction.