Many of us don't stop to question the medications our doctors prescribe. Rather, we assume that our doctors have our best interests at heart, and we do as we're told.

But in reality, it's pretty common for doctors to prescribe medications for conditions they were not initially intended to treat. When this happens, the drug in question is considered "off-label." An off-label drug is a prescription drug being used in a different manner from its intended use, as approved by the FDA.

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FDA drug approvals

When the FDA approves a drug, it includes instructions regarding its intended and appropriate use. If you're given a drug for its FDA-approved use, then you can rest assured that the FDA has carefully evaluated that drug's benefits and risks and has deemed it a safe choice for the condition at hand. Once the FDA approves a drug, however, doctors are free to prescribe it for reasons other than its approved use, and they often do so when they feel that it is medically appropriate.

Benefits of off-label drug use

While the practice of prescribing medications off-label might seem questionable, it actually has its benefits. In some cases, going off-label might be the only choice when dealing with rare or hard-to-treat diseases. In situations where a patient has exhausted all FDA-approved treatment options, a doctor might recommend going off-label to explore different avenues for treatment. This is common in the realm of cancer treatment, where drugs are commonly approved to treat some types of cancer, but not others.

Marketing off-label drugs

While it's perfectly legal for a doctor to prescribe off-label drugs, pharmaceutical companies must follow some rules regarding their marketing. Drug companies are not allowed to promote the medications they make for any type of off-label use -- a rule that has been the subject of several large lawsuits through the years. In other words, if a drug is approved by the FDA to treat seizures, but doctors get in the habit of prescribing it as a sleep aid, the company that makes that drug cannot advertise it as a sleep aid.

How off-label drugs help pharmaceutical companies

Just because pharma companies can't market their drugs for non-FDA-approved purposes doesn't mean they can't benefit when doctors prescribe them off-label. Medications that are widely adopted for off-label purposes can generate extra revenue for the companies that produce them. The more uses a drug has in practice, the more likely it is to be prescribed, and when this happens, pharmaceutical companies make money.

How off-label drugs impact patients

Doctors aren't actually required to inform their patients when they prescribe drugs off-label -- a fact that many find problematic and unethical. Furthermore, when medications are prescribed for off-label use, insurance companies might refuse to pay for them. If this happens, it's the patients who get stuck with the bill.

That's why it's important for patients to understand what they're being prescribed and to always check their coverage before filling prescriptions. Even if a drug is perfectly safe when used off-label, there may be financial repercussions to taking medication for purposes other than its approved use. 

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