contreindications

Contraindications are factors or conditions that make a medical intervention or treatment inadvisable because the risks outweigh potential benefits. They are identified to avoid harm to the patient. Contraindications are typically classified as absolute (the intervention should not be used under any circumstances) or relative (the intervention may be used with caution when benefits outweigh risks).

Common absolute contraindications include known severe allergies to the treatment or its components, pregnancy for certain drugs or procedures, and conditions that pose an immediate risk if the intervention is performed (for example active major bleeding with anticoagulation). Relative contraindications include comorbidities that increase risk, such as mild organ impairment, concurrent use of interacting medicines, or unstable medical status, where extra monitoring or alternative options may be considered.

Examples vary by intervention. Drug contraindications include avoiding a medication in patients with a history of anaphylaxis to it, or in those with severe hepatic or renal impairment. Vaccines may be contraindicated in severely immunocompromised individuals. Procedures may be avoided in patients with uncorrected coagulopathy or uncontrolled hypertension. In imaging, contrast media can be contraindicated in known contrast allergy or kidney disease.

Clinical assessment of contraindications involves reviewing medical history, current medications, allergies, and laboratory data; evaluating the immediacy and severity of the condition; and considering alternative therapies. Shared decision making and informed consent are important. Contraindications may be reconsidered as new evidence arises or as patient status changes.