Until recently, holistic and Ayurvedic cures that combine herbal medicines with yoga, massage and meditation were the most sought after by international visitors, but now centres providing conventional medicine are attracting a huge number of patients from abroad.
According to statistics, foreign patients account for 12% of the total in hospitals such as Breach Candy, Hindujas and Jaslok in Mumbai, the country's financial capital.
Dr KK Aggarwal, a leading cardiologist in Delhi and president of the Federation of National Capital Region Doctors, told Aljazeera.net: "Largely they are coming for organ transplant, knee replacement and open heart, hip and plastic surgery.
"Low-cost treatment is the ultimate factor weighing in India's favour while state of the art equipment and top class doctors also help attract foreign patients," he says.
While a liver transplant could cost $140,000 in Europe and double that in the US, it costs about $45,000 in some Indian hospitals such as Global Hospital in the southern city of Hyderabad.
Similarly, heart surgery in the US costs between $30,000 and $45,000 but only $5000 in the best hospital in India, he says.
G Krish, a British Indian who underwent heart bypass surgery at Delhi's Apollo Hospital, the largest chain of private hospitals in India, said: "The good hospitals here have world class facilities and doctors but cost one-tenth.
"In the UK we have to wait endlessly to get admission into hospitals under the state-sponsored health care which is very frustrating."
Krish said he appreciated the fact that "unlike in England there is no wait to get into the hospital and no rush to get out".
Patients have to join waiting lists
in the United Kingdom
According to Apollo Chairman, Dr Pratap C Reddy, India could earn more than $1 billion annually and create 40 million jobs by sub-contracting work from the British National Health Service (NHS) alone.
Medical treatment in the UK is free under the NHS but because of the long wait, some patients are forced to opt for exorbitant private medical care. Lately, however, a large number of them are heading to India for treatment.
Apollo's proposal to sub-contract work and thereby cut waiting time and costs is being studied by the British government.
Patients from poor countries in Asia, especially from neighbouring Bangladesh, Bhutan, Myanmar, Mauritius and Pakistan come to India because good treatment is not available at home. Their preference is the country's premier, government-owned All India Institute of Medical Sciences (AIIMS) in Delhi where treatment is even cheaper than in the private hospitals.
In Asia, India has to compete with Thailand and Singapore that have advanced medical facilities and built-in medical tourism, painstakingly promoted over the past two decades. The rush of foreign health tourists here is five to six times more than that in India.
Last year, more than 150,000 patients, mostly from Europe and the Middle East, came to India and the number is rising by 30% annually, according to official statistics.
A recent study conducted by the Confederation of Indian Industry (CII) and McKinsey consultants estimated that India could earn $2.3 billion through medical tourism over the next six years.
The study has also helped the sudden spurt in health tourism.
The Indian health and tourism ministries, both of which have special departments to promote health tourism, are much better geared to tap the potential now than in the past.
Private hospitals have their own public relations and marketing departments as also overseas offices that tie up with the travel industry and embassies to get patients from abroad. The Indian government too has a council for accreditation of hospitals where only the best are empanelled.
Thailand has advanced medical
According to CII-McKensy, a lot more needs to be done "much more professionally" to project the Indian medical industry. CII believes that India should replicate the Thai model which with its world-class infrastructure attracted one million patients in 2004.
The study also emphasised the need to undertake an international marketing campaign targeted at select countries besides setting up one-stop centres in key markets and streamlining visa facilities for medical visitors.
Aggarwal spoke of the need to remove bottlenecks such as "cuts and commissions wangled by the mediators, hidden costs and the language barrier".
Ayurvedics for arthritis
Language does not, however, seem to be a barrier for Dora Merzuoli from Florence who chose a private Ayurvedic centre in the Indian capital for her arthritis.
Merzouli, a volunteer with a Christian mission and a regular visitor to India, opted for a three-week massage therapy developed in Kerala, the south Indian state that pioneered health tourism in the country and annually attracts up to 500,000 health tourists.
She said she was "encouraged by the positive results" her friend, Sister Gemma, had for similar problems.
Gemma says she prefers the Ayurvedic treatment because it is "effective and without side effects".
In Kerala, rated as one of the 10 must-see destinations by National Geographic, tourism revolves around Ayurvedic cures and the state's tourist growth rate has been at 25% to 30% annually.
Lately however, even modern medical tourism has recorded a spurt and experts are optimistic that India, whose world class medical colleges turn out about 30,000 doctors annually, could soon become one of the top health tourism destinations in the world.