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What is a black box warning on a prescription drug?


A black box warning is the strictest warning put in the labeling of prescription drugs or drug products by the Food and Drug Administration (FDA) when there is reasonable evidence of an association of a serious hazard with the drug. It is basically a warning with a black box around it, hence the name. Having the black box around the warning means that an adverse reaction to the drug may lead to death or serious injury. It's based on clinical data or serious animal toxicity data in the absence of clinical data. Sometimes a black box warning is necessary at the time a new drug is approved. More commonly however, it is added after the drug has been approved and the FDA has received reports of adverse events. After the FDA confirms the serious risk, then depending on the severity of adverse event and in collaboration with the pharmaceutical company, a boxed warning is implemented. This does not mean the drug is contraindicated in any way, but just a means of communication from the FDA to prescribers to highlight the risk. As with any drug, there is a risk and benefit associated with taking the drug. The black box warning is to alert prescribers of the potential risk in prescribing this drug so they can take it into consideration. If you have concerns regarding your prescription, discuss with your physician.

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Answers to questions regarding information about medications or health conditions are not for diagnostic or treatment purposes and are not conclusive as to the presence or absence of any health condition. Consult your physician for diagnosis and treatment of your medical condition. The information provided is not a substitute for medical advice. Advances in medicine may cause this information to become outdated, invalid or subject to debate. Professional opinions and interpretations of the scientific literature may vary. Walgreens' terms of use and general warranty disclaimer apply to all services provided. If you are in need of immediate medical attention, contact your physician, poison control center or emergency medical professional. If you need to speak with a pharmacist for non-emergency matters, contact your local Walgreens pharmacist or call a pharmacist toll-free at 1 (877) 250-5823.

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