The incident came to light when video of the proceedings went viral on a messaging app.
A case has been registered against six persons including the girl's father and the 'Mantrik' (quack) at Chakur police station in Latur district.
Vikas Naik, deputy superintendent of police, Chakur, told PTI that an elderly woman is also an accused in the case.
Police today arrested Prabhakar Kesale (35), Gangadhar Shewale (65), Pandit Kore (37) and Dagadu Shewale (40), while a team has been sent to Bidar district of Karnataka to nab the quack.
The girl, a first year BA student, suffered from perennial stomach ache, DSP Naik said. Family members suspected that she was a victim of some black magic, and took her to a quack in Bidar district on June 4.
Another woman from the same village, who suffered from from epilepsy, accompanied her.
At Bidar, as a part of so-called treatment, both were beaten up mercilessly and forced to eat cow dung.
One of the accused shot video of the proceedings on mobile phone. Police took action after some senior police officers received forwarded video on their phones.
Latur police have registered a case under the Maharashtra Prevention and Eradication of Human Sacrifice and other Inhuman Evils and Aghori Practise and Black Magic Act, 2013.