Adverse reactions are most likely to occur when starting or discontinuing the drug, increasing or lowering the dose or when switching from one SSRI to another. Adverse reactions are often diagnosed as bipolar disorder when the symptoms may be entirely iatrogenic (treatment induced). Withdrawal, especially abrupt withdrawal, from any of these medications can cause severe neuropsychiatric and physical symptoms. It is important to withdraw extremely slowly from these drugs, often over a period of a year or more, under the supervision of a qualified and experienced specialist. Withdrawal is sometimes more severe than the original symptoms or problems.