Bhim Army chief Chandrashekhar Azad, arrested in connection with violence in old Delhi's Daryaganj area, moved court on Monday through his lawyer seeking a direction to the jail authorities to provide him treatment at Delhi's AIIMS.
The application claimed that Mr Azad was suffering from polycythemia, a disease of blood thickness, and "requires continuous checkup from the doctors concerned from AIIMS, who are supervising his treatment for a long time".
If the treatment was not provided urgently to Mr Azad, it might lead to cardiac arrest, the application moved through advocate Mehmood Pracha said.
It is likely to be taken up for hearing on Tuesday.
The plea sought a direction to the jail authorities or the Delhi Government to provide medical treatment to Azad.
The Bhim Army chief was sent to judicial custody on December 21 by a Delhi court.
Chandrashekhar Azad's Bhim Army had organised a march from Jama Masjid to Jantar Mantar against the amended Citizenship Act, despite not having police permission.
The marching protesters were stopped by police and paramilitary personnel near Delhi Gate, after which they turned violent and set a car on fire and damaged a few other vehicles. The police resorted to lathi-charge and used a water cannon to control the situation.