Does an Unexpected Complication Mean the Drug or Device Was Defective?

Not automatically. Medicine involves risks, and some side effects can occur even when a product works as intended. The legal question is usually more specific than whether something went wrong.

A dangerous drug or defective medical device claim may arise when a product has an unreasonable safety problem. Claims can also involve inadequate warnings about known risks, or defects introduced during manufacturing. Depending on the facts, a manufacturer or another company could bear responsibility.