Yes, doctors can prescribe non-FDA-approved drugs in several different situations, and it happens far more often than most people realize. The most common scenario is off-label prescribing, where a doctor uses an FDA-approved drug for a purpose, dose, or patient population the FDA hasn’t specifically reviewed. But doctors can also prescribe completely unapproved drugs through special FDA pathways, order custom-made compounded medications, and even prescribe certain older drugs that have been sold in the U.S. for decades without ever going through formal FDA approval.
Off-Label Prescribing: The Most Common Route
Once the FDA approves a drug for any use, doctors are generally free to prescribe it for other uses they consider medically appropriate. The FDA itself acknowledges this, stating that healthcare providers “may prescribe the drug for an unapproved use when they judge that it is medically appropriate for their patient.” This practice is called off-label prescribing, and it’s a routine part of medicine rather than some rare exception.
Off-label use is especially common in pediatrics, oncology, and psychiatry. In children, roughly 36% to 47% of prescribed medications in the U.S. are used off-label, largely because only about 12% of clinical trials have focused on diseases that disproportionately affect kids. Many drugs simply haven’t been formally studied in younger patients, so pediatricians rely on clinical evidence and professional guidelines to adapt adult treatments. Cancer doctors frequently use approved chemotherapy drugs in combinations or sequences the FDA hasn’t specifically blessed, guided by evolving research and treatment guidelines from organizations like the National Comprehensive Cancer Network.
The FDA does not regulate the practice of medicine. It regulates drug manufacturers, controlling what companies can market and advertise. Your doctor’s actual prescribing decisions fall under the oversight of state medical licensing boards, which hold physicians to the standard of care in their field. As one state medical board put it, it remains “the sole and esteemed role of the licensed practitioner” to consider all available information and treat patients in the most appropriate way, under the regulation of their licensing board.
What Off-Label Prescribing Means for Liability
Prescribing off-label is legal, but it’s not a free pass. Doctors are still held to the same malpractice standards whether they prescribe on-label or off-label. The key question in any legal dispute is whether the prescription met the accepted standard of care. In general, the more published scientific evidence supporting a particular off-label use, the more likely it is to be considered appropriate practice.
Informed consent becomes especially important with off-label prescriptions. Because these uses haven’t gone through the same FDA review process, there may be more unknowns about risks and side effects. Doctors are expected to discuss the nature of the treatment, its potential risks and benefits, alternatives (including doing nothing), and to document that conversation. The “why” behind the decision matters: a doctor should be able to articulate a clear clinical or scientific reason this particular drug makes sense for this particular patient. If a doctor can’t explain their reasoning, that’s a red flag both medically and legally.
Expanded Access for Experimental Drugs
When no approved drug will work and no clinical trial is available, doctors can request access to investigational drugs that haven’t been approved for any use yet. The FDA calls this “expanded access,” sometimes known as compassionate use. This pathway exists for patients with serious or immediately life-threatening conditions who have no comparable or satisfactory alternative treatment.
The process involves several steps. Your doctor must first confirm that no suitable clinical trial exists for you, either because none are running, you don’t qualify, or the trial site is too far away. They then need to contact the drug’s manufacturer directly, because the company must agree to provide the investigational product. There’s no guarantee a manufacturer will say yes. If the company agrees, your doctor takes on significant responsibility: submitting a formal request to the FDA, obtaining your informed consent, managing your care while you’re on the drug, and filing follow-up reports with the FDA about how the treatment goes.
The FDA approves the vast majority of expanded access requests it receives, often within days for emergency cases. But the real bottleneck is usually getting the manufacturer on board and navigating the paperwork. This is not a casual prescription. It’s a structured process designed to balance patient access against the real risks of using a drug whose safety profile is still being studied.
Compounded Medications
Compounded drugs are custom-made medications prepared by pharmacies, and they are not FDA-approved. The FDA does not review them for safety, effectiveness, or quality before they reach patients. Despite this, doctors prescribe them regularly for patients who need something a standard manufactured drug can’t provide: a different dosage form, a version without a specific allergen or dye, or a combination not commercially available.
Federal law carves out two categories. Under one provision, traditional compounding pharmacies can prepare medications based on individual patient prescriptions from a doctor. Under a second provision created in 2013, “outsourcing facilities” can produce compounded drugs in larger batches without patient-specific prescriptions, though they must follow stricter manufacturing standards. In both cases, the drugs themselves remain unapproved by the FDA. Your doctor takes on added clinical judgment when prescribing a compounded medication, since there’s no FDA-reviewed label to rely on for dosing, interactions, or side effects.
Drugs That Never Got FDA Approval
There’s a lesser-known category that surprises most people: hundreds of drug products are currently sold in the United States without ever receiving FDA approval. Most are decades old. Before 1938, drugs didn’t need any FDA review at all. The 1938 law required evidence of safety but not effectiveness, and a 1962 amendment added the effectiveness requirement. The government launched a review to retroactively evaluate drugs approved only for safety, but many products slipped through the cracks and simply stayed on the market.
In 2006, the FDA created the Unapproved Drugs Initiative to address this backlog, pushing manufacturers to either obtain proper approval or pull their products. But the process has been slow, and some unapproved drugs remain available. Doctors can and do prescribe these products, though many may not even realize a particular medication lacks formal FDA approval.
Insurance Coverage for Non-Approved Uses
Whether your insurance will pay for a non-FDA-approved drug use depends on the type of use and the evidence behind it. Medicare covers off-label drug uses if the use is considered “medically accepted,” which it defines by checking whether the use is supported in recognized drug reference guides known as compendia. These are large, regularly updated databases that evaluate published evidence on drug uses. If a major compendium lists the off-label use with a supportive rating, Medicare will generally cover it.
Private insurers often follow similar logic but set their own rules. Some are more restrictive than Medicare, requiring prior authorization or denying coverage for off-label uses that lack strong compendium support. If your doctor prescribes something off-label and your insurer refuses to pay, asking your doctor to submit a letter of medical necessity with supporting evidence can sometimes reverse the decision. For expanded access drugs and compounded medications, coverage is even less predictable, and you may face out-of-pocket costs.