The incident had occurred in August but came to light now when the victim, a physiotherapist, lodged a complaint.
The accused, identified only as Manoj, called up the survivor to his house and offered her sedative-laced drink. He later allegedly raped her, they said, adding the two were neighbours.
"After the incident, the accused reportedly started threatening the woman, after which she lodged a complaint," a police officer said.
Following the complaint, a case was registered under IPC, Rajendra Nagar Police Station Inspector V Umender said, adding further probe was on.