Moderate reactions include those listed as mild if a person considers them to be distinctly annoying, distressing, or intolerable. Mild or moderate adverse drug reactions do not necessarily mean that a drug must be discontinued, especially if no suitable alternative is available. Sometimes drugs cause severe reactions that are potentially life-threatening, although they are relatively rare. People who develop a severe reaction usually must stop using the drug and have the reaction treated. They'll use every possible means to cope with the serious adverse reaction.
Every drug has the potential to cause harm as well as to do good.
Whenever doctors consider prescribing a drug, they must weigh the possible risks against the expected benefits. Use of a drug isn't justified unless the expected benefits outweigh the possible risks. Doctors must also consider the likely outcome of withholding the drug. Potential benefits and risks can seldom be determined with mathematical precision. When assessing the benefits and risks of prescribing a drug, doctors consider the severity of the disorder being treated and the impact it's having on the patient's quality of life.