Whenever I hear of young adults with the type of disabling depression you describe -- and especially when they are men -- I worry that they may go on to have a more serious condition called bipolar disorder, also known as manic-depression.

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His wife was diagnosed with manic depression and his son became addicted to heroin - at one point he had to buy drugs for him.

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Van Gogh, Mr Gayford says, suffered from bi-polar disorder, a severe form of manic depression which can now be treated with lithium but which then was undiagnosed.

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