What is a Black Box Warning for a Drug?

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Question: What is a Black Box Warning for a Drug?

From a reader: I have rheumatoid arthritis and my doctor recently prescribed Enbrel, which I take by injection. The nurse in the office told me that Enbrel has something called a black box warning and she gave me an Enbrel medication guide. What is a black box warning and do I need to be concerned?


I’m sorry to hear that you have rheumatoid arthritis.

My understanding is that Enbrel can be an effective medication and I hope that it helps you with your condition.

A black box warning appears on the label of a prescription medication to alert you and your healthcare provider about any important safety concerns, such as serious side effects or life-threatening risks.

A black box warning, also known as a “black label warning” or “boxed warning,” is named for the black border surrounding the text of the warning that appears on the package insert, label, and other literature describing the medication (such as magazine advertising). It is the most serious medication warning required by the U.S. Food and Drug Administration (FDA).

Enbrel’s Black Box Warning

Enbrel, a widely-used drug for the treatment of rheumatoid arthritis and psoriasis, has a black box warning from the FDA because of the risk of tuberculosis (TB) and other serious infections, which for some patients can lead to hospitalization or death.

In March 2008, Amgen and Wyeth, the drug companies that make Enbrel, wrote a letter to physicians to let them know about Enbrel's black box warning.

Enbrel, given by injection, is a type of medication known as a tumor necrosis factor (TNF) blocker that blocks the action of a substance your body makes called TNF.

People with rheumatoid arthritis, psoriasis, and some other diseases affecting their immune system may have too much TNF in their bodies. Enbrel, by reducing the amount of TNF in your body, helps to treat your disease. However, Enbrel can also make it more difficult for your body’s immune system to fight infections.

Although the risk is small, your doctor should have tested you for TB (PPD skin test) before starting Enbrel and test you again during treatment. Your doctor will want to know if you have any signs of infection such as a fever, cough, or flu-like symptoms. If you do have any infections, including TB, your doctor may want to treat you with antibiotics or have you stop taking Enbrel.

It is important that you and your doctor understand the benefits and risks of treatment.

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