The practice of using leeches to treat ailments is an ancient therapy, but it appears their so-called healing power are still being used today in medical practice.
Leeches are a medically approved treatment for patients in one clinic in Tehran, with the therapy being recommended for back pain, diabetes and even cardiovascular diseases.
Also known as hirudotherapy, it is one of the centuries-old therapies used in Iranian traditional medicine that has found its way to the modern world.
It is believed that leech saliva helps to thin the blood and is also thought to relieve pain and can act as an anaesthetic.
The US government approved the use of leeches for healing skin grafts and for helping circulation in 2004.
While they are not a common use of medicine to treat patients, leeches are farmed for medicinal purposes in the UK.
They can be administered at leech therapy clinics with the approval of a GP.
There are certain risks associated with the treatment. For example, leech contain bacteria in their gut that helps them digest blood but can lead to infection. Also, patients have been known to bleed for several hours after the treatment.
Recent studies have shown that leech therapy, among other things, has reduced the side effects of plastic and reconstructive surgery, help in pain management caused by arthritis, heal complicated varicose veins and the ulcers of diabetic patients.