By CHRISTIAN GYSIN

Last updated at 23:04 13 March 2008

A schoolboy who was taking Ritalin has been found hanged in his bedroom.

Anthony Cole, 15, had Attention Deficit Hyperactivity Disorder and recently had his prescription for the drug increased.

Recent research claims that Ritalin, also used to combat hyperactivity in children, has led to many developing "manic and psychotic" symptoms.

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Anthony Cole was found hanging after his Ritalin prescription had been increased

The drug has previously faced criticism for side effects that include mood swings and sleeping difficulties.

Anthony's father said he had noticed the schoolboy becoming snappy and acting as if in a trance shortly before he died.

Days earlier, he had asked his mother how to write a will and enquired about life insurance.

On Saturday, an hour after cuddling her and telling his family he loved them, Anthony was found dead by his father.

Colin, 51, of Conniburrow, Milton Keynes, said yesterday: "He was just so cheerful and always smiling, but I think he bottled a lot of his feelings up.

"He had said he was worried about his GCSEs and that bigger boys at school had been picking on him.

"He had his problems but on school holidays he seemed so much calmer and happier.

"But when he went back to school after the recent half-term break he became really snappy and tense. Sometimes he acted like he was in a trance."

"He was a very inquisitive boy, he was interested in electronics and mechanics. On Saturday he was watching me fix a plug and asking lots of questions.

"He disappeared to his bedroom and about an hour later we called him down for lunch. But when he didn't reply I went upstairs and found him hanging there."

Anthony's mother Tina, 45, added: "I was peeling potatoes with him when he asked me about making a will.

"I was really shocked but I thought it was just his inquisitive nature. We have a lot of unanswered questions.

"Sadly Anthony has taken many of the answers with him."

Anthony, who leaves his twin brother and sister, ten, and sister, 13, was prescribed Ritalin six years ago when he was diagnosed with ADHD. An inquest into his death will take place in June.

Two years ago, an investigation by the U.S. authorities said the drug should carry a warning that those taking it could suffer from mania and aggression.

The drug and related brands have been blamed for 11 children's deaths in the UK.