Drew Scientific was the first to attract support. The shares surged from around 30p to 240p but fell 47.5p to 147.5p.
On Friday Tepnel Life took off and remained strong with the price jumping a further 49p to 125.5p in busy trading.
Others, in varying degrees, have caught the fever. Chiroscience, forging a link with a Nestle's subsidiary Alcon Laboratories, added 7p to 371p and Celltech and Cortecs International moved ahead.
Even strugglers like Haemocell, unchanged at 5.75p, and Enviromed, 2.5p higher at 20p, have been brushed by the sudden desire to hit the medical jackpot. Biocure, making diabetes kits, gained 5p to 30.5p. The company is raising cash through a 9p-a-share rights issue and is related to the Monaco-based entrepreneur Michael Charlton.
Shield, with its heart disease detection test, is clearly the health stakes winner so far this year. The shares, in an erratic day's trading, crashed from their peak when some of its US tests proved inconclusive. But they have steadied, helped by the ending of a tap of institutional selling as a stake was reduced.
Drew, which placed shares with institutions at 52p recently, said last week it was hoping to extend its technology to heart disease. Its headlong gallop appears to have been reined back by stockbroker Wise Speke which cautioned the shares could be running ahead of events.
The excitement was not confined to the second-liners. For the second trading day SmithKline Beecham attracted US support, leading blue chips higher with a 35.5p gain to 893p. Medeva put on 6.5p to 312.5p and Zeneca, reflecting the launch of its Zomig migraine treatment, rose 22.5p to 1,762.5p.
Even Glaxo Wellcome, which lost its latest Zantac infringement case in the US, confined its discomfort to a modest 4p fall to 1,086p.
The rest of the stock market was in more confident form with Footsie climbing 35.1 points - a two-day gain of 55.1 - to 4,271.7. The start of the new tax year, however, did not have dealers on their toes with turnover at best moderate. Government stocks had a volatile session. Hit early by talk of big US sales, they closed with gains of around half- a-point.
Financials turned in a strong display with Abbey National up 18.5p at 760.5p and Barclays 24p higher at 1,053p. NatWest Securities was said to be advocating the attractions of banking shares.
PowerGen was out of step, falling 6.5p to 609.5p after warning analysts profits for the year just ended would be in the pounds 530m to pounds 585m range, below some estimates.
The generator was not the only utility feeling the pinch. Talk of tax curbs and higher rates took its toll with Thames Water off 11.5p to 665p.
Oils were in better shape although British-Borneo Petroleum Syndicate continued to reflect its disappointing Gulf of Mexico drilling report, falling 89p to 1,302.5p.
Melrose, firmed to 20.5p; the group is being split with deputy chairman Robert Adair departing with some of the group's interests. He is paying pounds 2.5m in cash and cancelling half his 34 per cent stake.
BG had another upbeat session as the conviction grew its confrontation with its industry regulator will be less wounding than at one time thought. The shares gained 5p to 178.5p, equalling their high.
RJB Mining, figures today, improved 35.5p to 390.5p following its "clean coal" link with National Power, off 3p at 502.5p.
Mini-conglomerate Thomas Jourdan gained 3.5p to 67p as investors, including former Suter chief David Abell, moved to oust chairman Keith Whitten.
Profit warnings hit Universal Salvage 67.5p to 135p and Pordum Foods, 1p to 1.5p.
The volume was turned down at Verity, off 4p at 48.5p. ED & F Man, the commodities group, fell 7.5p to 178.5p on worries over its links with Cuba.
Prism Rail was shunted 50p lower to 305p on the Save Our Railways report, alleging heavy losses. But the shares rallied to 345p as the company said it "totally refutes" the report.
Masthead Insurance held at a 122p peak. Goshawk Insurance, thought to be stalking Matheson Lloyd's investment trust, has 6.5 per cent.