About 2,560 tonnes of the leafy plant khat are imported to the UK every year. Users chew the bitter leaves of this natural stimulant. It is supposed to make them more alert and raise energy levels, with effects similar to amphetamine but less intense. However khat users may also experience mental health problems, such as euphoria followed by depression, while people who are genetically predisposed are extremely vulnerable to psychosis. Since 24 June 2014 khat is classified as banned class C drug in the UK.