The retailer said the roll-out entails a£5 million investment. The Wal-Mart owned grocer plans to open 15 pharmacies this year, with a further 33 to be unveiled by 2007.
The pharmacies will have licence exemptions that allow them to open for 100 hours a week. The exemptions require the pharmacies to be situated in a retail space larger than 161,450 sq ft (15,000 sq m).
Asda, which has been a firm advocate of the relaxation of pharmacy rules, urged the Government to go for full deregulation when it reviews the sector next year. It cited a call from the Office of Fair Trading (OFT) for the deregulation of pharmacies.
An Asda spokesman said: 'We believe the current situation is anti-competitive. While some relaxation is good, it's still not what the OFT is asking for. The exemptions are great, but at the end of the day they are still exemptions. We would like to see a pharmacy in every store.'
Asda operates 83 in-store pharmacies at present, which trade for 83 hours a week.