This page (I don’t know how trustworthy it is) claimed on 19th May:
“Three days [ago] Goa issued a Government Order for mass prophylaxis using ivermectin for the people of Goa”, said Dr Suryakant. Goa is the first state in India to use ivermectin in this way, he emphasised. Uttar Pradesh was the first state to issue a Government Order for the use of ivermectin for treatment and prophylaxis for asymptomatic and mild cases of covid-19 and for prophylaxis of health care workers and home contacts.
This page (I don’t know how trustworthy it is) claimed on 19th May: