What "powerful drug" if I may ask is your friend taking that could "kill her?"
Ivermectin will give her some relief. It won't kill her. I recommend she try powder praziquantel, which is mild stuff compared to other drugs like permethrin. She could take it orally, but if she doesn't want to ingest it, then at least dissolve it in water and apply to lesions.
She needs systemic meds in combinations because parasites exist in different stages; drugs treat stages, not the species on the whole.
parasites can live a looooong time. She cannot pick this thing away.
Why are you here on CZ, and not she? This community can help her to cope.