Almost all medications can have adverse side effects under the right circumstances. Even over-the-counter medications like aspirin cause thousands of injuries and deaths every year. Not all side effects can be the basis for a lawsuit. When a condition is a known side effect of the drug a patient is taking, and the patient was advised about that risk, the side effect can be an acceptable consequence of medication. In prescription medications, side effects may be legally actionable in several circumstances. Generally, side effects may be actionable when their impact is worse than the condition the drug was supposed to treat. Additionally, if a side effect was unknown but the FDA approved the drug, patients who later develop that side effect may have a case. Finally, if a doctor or pharmacist's error led to the patient taking a medication with dangerous side effects, the injured person can also sue.