Jagdeep Dhankhar, who stepped down as the vice president citing health reasons, has been keeping unwell, even though he appeared lively and energetic in Rajya Sabha, which he presided over as chairperson.
He was admitted to the AIIMS in New Delhi for a few days in March, following which he was advised to curtail his trips outside the national capital for a while.
In June, on a visit to Nainital in Uttarakhand, Dhankhar had collapsed at the Kumaon University.
Officials had then said the day was "unusually hot" and the hall in which he was addressing a gathering was "stuffy". They said he had fainted briefly, and his personal security officer was quick to hold him.
Earlier this month, on a visit to Kerala, the former vice president was seen being held by his spouse, Sudesh, and an aide as he was walking.
Again, on July 17, Dhankhar felt unwell when he went to Vatika developed by Delhi LG VK Saxena.
It took him a few minutes to recover as his spouse offered him water.
In his resignation letter to President Droupadi Murmu on Monday evening, Dhankhar said he was stepping down with immediate effect to "prioritise health care".
"To prioritise health care and abide by medical advice, I hereby resign as Vice President of India, effective immediately, in accordance with Article 67(a) of the Constitution," he said.
Dhankhar, 74, assumed office in August 2022 and his tenure was till August 2027. The resignation of Dhankhar, the Rajya Sabha Chairman, came on the first day of the Monsoon session of Parliament.