Punjab Chief Minister Parkash Singh Badal was admitted to the Post-Graduate Institute of Medical Education and Research (PGIMER) hospital late on Friday night with minor infection.
Doctors said that Badal was stable and kept under observation.
Badal, on Friday evening, was taken to a private hospital in Nawanshahr town in Punjab after he felt cold and complained of uneasiness.
He was taken to the hospital in Nawanshahr, 80 km from here, where doctors treated him with a nebulizer and steam.
Badal, who attended a 'Sangat Darshan' (meeting with public) function earlier in the town, was, however, discharged after some time.
Doctors said cold wave conditions could have caused Badal's indisposition as he attended the 'Sangat Darshan' programme in the open.
Badal, 88, is the oldest chief minister in the country.