USP Not many places have a hot spa pool with hundreds of voracious fish. It's all part of a treatment that claims to heal psoriasis at this remote spa 5,000 feet high in the Central Anatolia region of Turkey.

AMBIENCE Accommodation is basic but clean — think 1970s youth hostel. The public areas in the hotel are smoke-filled, particularly the television room in the evenings, where Turkish guests meet to play cards and dominoes. Bring a DVD player, iPod and books.

EXPERIENCE Good, although the fish spa pools are the only game in town, and the only “therapist” other than the fish is an on-site nurse who doesn’t speak English, although the manager can translate. The psoriasis treatment regimen is not for the fainthearted. Twenty-one days of twice-daily, four-hour bathing sessions in the fish pools is prescribed, plus drinking 1.5 litres of spa water a day on an empty stomach. However, many of the guests saw a major improvement in their skin condition during the treatment.

FOOD Tasty local meals — lots of aubergine dishes, fresh tomato salads and local lamb.

IN-CROWD The hotel caters for people who are willing to try anything to tackle their psoriasis. Repeat visitors come from all over the world.

WALLET WATCH $22 (£12) a day full board, plus $50 a day for access to the pools.

NEED TO KNOW Balikli Kaplica Spa, Kangal, Sivas, Turkey (00 90 346 469 1151/53/54). Turkish Airlines fly via Istanbul to Sivas on Fridays and Sundays: www.thy.com

Read the full article: The spa sits beside a snow-melt swollen river, in a valley 1,600m (5,250ft) up in the mountains of this remote agricultural region. It has made a name for itself, and its resident "doctor fish" (Garra rufa obtusa), as a treatment for psoriasis, a painful skin complaint that afflicts about 2 per cent of the UK population.

The healing powers of the fish were discovered by a shepherd and his flock in 1917. He stumbled into marshy ground with an injured foot and found the open wound besieged by fish. The wound healed and eventually word got to the outside world about these efficacious little creatures.

The combination of the metal-rich mineral waters, the fish and mountain sunlight have been helping psoriasis sufferers ever since. The first rudimentary spa was built here in the 1950s. The present hotel buildings, spa pools and changing facilities were built in the 1970s. There are two open-air and two indoor pools, each home to hundreds of small fish.

The fish have made a name for themselves as bio-therapists. Members of the carp and minnow family, the two species of fish in the spa pools appear to survive the 37 degree water with no ill effects. I ventured into one of the outdoor spa pools.

The fish were hungry after a spring when few visitors had braved the blood warm waters while being pelted by hailstones or snow.

It might sound masochistic but it was suprisingly fun. The normally vegetarian fish homed in on areas of dry skin, around my heels and, particularly ticklish, the soles of my feet. But for a psoriasis sufferer, the fish target the plaques - areas of sore, red and thickened skin. The more benign beasts, the "lickers", rarely exceed a couple of inches in length. They cruise their way along the surface of your skin, gently scraping off and munching loose skin flakes. Less gentle are the aptly named "strikers", who employ more of a hit-and-run mechanism. Very fast, they dart in, take a chunk out of you and swim off to enjoy their spoils at leisure.

According to the British Association of Dermatologists, this removal of superfluous skin flakes aids sufferers because "it may help topical medications to penetrate, which is why some people may notice some improvement, but we are not aware of any other proven benefits".

The psoriasis treatment regimen is not for the fainthearted. Twenty-one days of twice-daily, four-hour bathing sessions in the fish pools is prescribed, plus drinking 1.5 litres of spa water a day on an empty stomach. However, many of the guests saw a major improvement in their skin condition during the treatment.

Paul 36, from Northern Ireland, has had psoriasis since the age of 14. "I've tried steroid creams, Chinese herbs, acupuncture, you name it." But he felt the spa did make a difference. "I definitely saw an improvement in my skin, but it's hard to say whether it's the water or the fish." Personally speaking, I have an idea that there are easier ways to exfoliate my feet, but probably none half as much fun.

IS IT FISHY OR NOT?

A paper published in the Journal of Dermatology in 2000 about the "doctor fish" of Kangal followed a small sample of patients at the spa under the supervision of a dermatologist. It concluded somewhat ambiguously that it "may be effective and useful for psoriasis patients". Dr Martin Grassberger, of the Medical University of Vienna, has done a more recent study which indicated clear benefits to more than 70 per cent of patients and a mean remission time of over eight months.

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