An ADR is a special type of ADE in which a causative relationship can be shown. ADRs may be classified by e. Such reactions are usually due to inappropriate dosage, especially drug of choice for diseases pdf drug elimination is impaired. Severity is a point on an arbitrary scale of intensity of the adverse event in question.
The terms “severe” and “serious” when applied to adverse events are technically very different. They are easily confused but can not be used interchangeably, requiring care in usage. A headache is severe, if it causes intense pain. There are scales like “visual analog scale” that help clinicians assess the severity.