Hassan, 83, was hospitalised twice in the last few weeks in Karachi after he suffered from a chest infection.
"He is better now and resting at home," Arif Mehdi, the singer's son, told PTI on phone from Karachi.
"We plan to take him to India in March for treatment. We had sent his medical reports to a hospital in New Delhi and sought an appointment, and this has been given," said Mehdi.
Hassan was born into a family of traditional musicians at Luna village in India's Rajasthan state in 1927. His family migrated to Pakistan at the time of partition. Hassan, who has a huge following in the subcontinent, cut back on his performances in the late 1980s due to illness.
On hearing of Hassan's financial problems in 2009, Prime Minister Yousuf Raza Gilani announced that the government would provide Rs 50,000 a month as aid to the singer.