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Discovery raises hopes on allergies

Scientists have accidentally rediscovered a cannabis folk remedy after finding active ingredients in the drug can help allergy management.

The research, conducted on mice, points the way towards new cannabis-based treatments for irritated skin.

Extracts from the hemp plant were traditionally used to treat inflammation and could even be bought from chemists in the early part of the 20th century.

But fears about the intoxicating effects of tetrahydrocannabinol (THC), the chemical that causes the cannabis "high", led to a ban on sales in the 1930s.

Scientists now believe that cannabis skin lotion, in a safe form too diluted to harm the brain, could make a comeback to help fight allergic reactions.

The animals were originally genetically engineered so they could not respond to cannabinoids, either THC or its natural equivalents generated in the brain.

Unexpectedly, the skin around ear clips put on the mice to identify them became red and sore.

The scientists realised that this means cannabinoids act just like a brake, preventing the immune system from running out of control and causing inflammation.

The scientists from the University of Bonn in Germany confirmed their suspicions by dabbing THC ointment on the skin of mice exposed to allergens.

Professor Thomas Tuting, a member of the team, said: "If we dabbed THC solution on to the animals' skin shortly before and after applying the allergen, a lot less swelling occurred than normal.

"The THC attaches itself to the cannabinoid receptors and activates them. In this way, the active substance reduces the allergic reaction."

University of Bonn

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