Azad told reporters then that Gandhi was suffering from "common cold and headache" and had taken some medicines that did not suit her.
Another Congress leader who did not wish to be identified by name, however, said that Gandhi had complained of chest pain -- shortly before the Lok Sabha took for voting numerous amendments to the bill.
Accompanied by central minister Kumari Selja and her son and Congress vice president Rahul Gandhi, Gandhi was rushed to AIIMS Monday night.
According to Azad, doctors found "nothing abnormal" with her condition and declared that all her health parameters were "perfect".
Nevertheless, the doctors decided to keep her under observation and discharged her around 1.30 a.m. Tuesday.
After Gandhi was taken to AIIMS, Prime Minister Manmohan Singh and numerous Congress leaders including Delhi's Chief Minister Sheila Dikshit called on her at the hospital.
"There is nothing to worry, some medicine did not suit her," Congress leader Janardan Dwivedi told crowds gathered at the hospital.