The announcement came as the capital Delhi imposed fresh restrictions to deal with a surge in Omicron cases.
India's Health Minister Mansukh Mandaviya said that the country's drug regulator has given emergency use authorisation to vaccines Covovax, Corbevax and an antiviral drug in a “single day” as the threat of a third wave looms.
The antiviral tablet Molnupiravir will be given to adult patients suffering from Covid-19.
The drug, made by US pharmaceutical company Merck, is thought to dramatically reduce hospital admissions among vulnerable and elderly people diagnosed with Covid-19.
The US medicines regulator, the Food and Drug Administration, authorised the pill for home use on December 23.
Corbevax, the country's first RBD protein subunit vaccine, will be made by Hyderabad-based firm Biological-E, while Covovax will be developed by the Serum Institute of India, the minister said. Protein subunit vaccines use a harmless “fragment” of Covid-19 to trigger an immune response.
Tuesday's fresh approvals take the number of vaccines in India to eight, but the country is largely using Oxford/AstraZeneca's Covishield and home-grown Covaxin to immunise about 950 million adults.
The government last week said it will vaccinate children between the ages of 15 and 18, and on Monday approved Covaxin for immunising them.
It also announced that it would offer booster shots to frontline workers and vulnerable people.
The fresh preventive measures come amid a spike in the number of highly transmissible Omicron infections in the country, with cases reaching 655 on Tuesday.
India has averaged around 7,000 cases a day in the past three weeks, with another 6,358 positive cases and 293 deaths recorded on Tuesday.
But cases have risen sharply in the capital Delhi in recent days, prompting the government to sound a yellow alert on Tuesday.
Delhi on Monday identified more than 300 cases, the highest single daily rise in infections since June.
The alert will allow the government to close down schools and colleges, restrict gatherings at weddings and funerals, as well as impose caps on shops and businesses.
The city has already imposed a night curfew to deal with a surge in cases following a devastating wave in April and May of this year, that saw up to 30,000 cases a day.
Several other Indian states and cities have also imposed restrictions and night curfews to contain the spread of the virus during the festive season.