What They Are
According to MedicineNet side effects as problems that occur when treatment exceeds the desired effect, or when undesirable or bothersome symptoms occur alongside the therapeutic treatment. In other words, side effects are the body’s physical or psychological responses that result from the presence of a drug in the body. Side effects are generally unintended actions that the drug has when it is in the body, that occur alongside the desired effect.
For example, a person who takes anti-anxiety medications may notice that, while taking the drug, heart rate slows and the pupils dilate. These are not the main actions of the drug, but they occur while the drug is in the body.
Most simply, if the drug is stopped, the side effects will stop. However, this is explained a bit more in the next section.
When They Occur
According to WebMD side effects generally occur while a person is taking the drug in question. In particular, side effects can begin to occur as soon as the first dose; otherwise, they may occur once the person has achieved the desired treatment concentration of the drug in the body. The amount of time this takes varies, depending on the type of drug. However, the drug isn’t generally having an effect on the body until it reaches a therapeutic concentration, so it often also takes that long for any side effects to become apparent, unless they are adverse reactions, such as allergies to the chemicals in the drug.
While side effects can continue to occur after the person has stopped taking the drug, they are not a result of the person ceasing intake. The side effects that may continue are a result of the drug’s effect on the body rather than its removal. As a result, most side effects cease quickly after a drug is stopped.
What They Look Like
Often, side effects occur in direct relation to the drug being used. Using the same examples as the withdrawal section, above, an individual taking a stimulant may experience side effects of rapid heart rate or jitters, along with paranoia or hyperfocus. On the other hand, side effects that result from a person taking a depressant include slowed heart rate and breathing, sleepiness, and inability to concentrate.
In other cases, side effects are not necessarily related to the drug’s action in the body. For example, some antibiotics, which are used to treat bacterial infections, can cause anxiety or panic as a side effect.