A compounded medication is a drug that’s custom-made for a specific patient, typically by a pharmacist who combines, mixes, or alters ingredients to create a version that isn’t available off the shelf. This might mean turning a pill into a liquid for a child who can’t swallow tablets, removing a dye that triggers a patient’s allergy, or combining multiple medications into a single dose. Compounding fills the gap when standard, FDA-approved drugs don’t work for a particular person’s needs.
Why a Doctor Would Prescribe a Compounded Drug
The most common reason is simple: the commercially available version of a medication doesn’t suit the patient. A child may need a smaller dose in liquid form. An adult might be allergic to an inactive ingredient like a preservative, filler, or dye used in the mass-produced version. Some patients need a medication combined into a topical cream instead of an oral pill, or they need two drugs mixed into one preparation for convenience.
Compounding also plays a role during drug shortages. When an FDA-approved medication becomes temporarily unavailable, compounding pharmacies can legally prepare versions of that drug to keep patients treated. Hospitals and clinics rely on compounded drugs regularly for patients whose medical situations don’t line up neatly with what’s on pharmacy shelves.
How Compounding Works
A licensed pharmacist (or in some cases a physician) prepares the drug based on a prescription written for a specific patient. The pharmacist sources raw active ingredients from registered suppliers, then combines them with inactive ingredients to create the final product in whatever form the patient needs: a capsule, liquid, cream, suppository, or injection.
There are two broad categories. Non-sterile compounding covers things like flavored oral liquids, custom-strength creams, and capsules with adjusted doses. These are prepared on clean workspaces but don’t require the extreme contamination controls of an operating room. Sterile compounding covers injectable drugs, eye drops, and IV solutions, which must be prepared in highly controlled environments because they enter the body in ways that bypass its natural defenses against bacteria and fungi.
The United States Pharmacopeia sets the technical standards pharmacies must follow. Separate chapters govern non-sterile preparations, sterile preparations, and the handling of hazardous drugs, each with its own requirements for equipment, environment, testing, and shelf life.
Two Types of Compounding Facilities
Federal law creates two distinct paths for compounding, each with different rules and oversight levels.
Traditional compounding pharmacies operate under Section 503A of federal law. These are your local or specialty pharmacies where a licensed pharmacist fills an individual prescription for a specific, named patient. They can prepare small batches in advance based on a history of receiving similar prescriptions, but they can’t mass-produce drugs or make copies of commercially available products on a routine basis. These pharmacies are primarily regulated by state pharmacy boards.
Outsourcing facilities operate under Section 503B. These are larger-scale operations that registered voluntarily with the FDA and can compound drugs without patient-specific prescriptions, supplying hospitals and clinics in bulk. In exchange for that flexibility, they must follow the same manufacturing quality standards (called current good manufacturing practices) that large pharmaceutical companies follow. The FDA inspects them on a risk-based schedule, and they’re required to report any adverse events linked to their products.
How Compounded Drugs Differ From FDA-Approved Drugs
The critical distinction is this: compounded medications are not evaluated by the FDA for safety, effectiveness, or quality before they reach patients. FDA-approved drugs go through clinical trials, manufacturing inspections, and a formal review process. Compounded drugs skip all of that. They’re exempt from the standard approval requirements because they’re intended to fill individual patient needs that approved products can’t meet.
This doesn’t mean compounded drugs are unregulated. Pharmacies must use ingredients that meet pharmacopeia standards, source active ingredients from FDA-registered facilities, and maintain valid certificates of analysis for their raw materials. But the finished product itself isn’t tested or verified by an outside agency the way a commercial drug would be.
Safety Risks to Be Aware Of
The reduced oversight creates real risks. The two main categories of concern are contamination and inaccurate potency. A compounded drug might contain too much or too little of the active ingredient, or it might be contaminated with bacteria or fungi if sterile procedures weren’t followed properly.
The most notorious example occurred when a compounding facility called the New England Compounding Center shipped injectable steroid preparations contaminated with environmental fungi. The FDA investigation found fungal contamination in unopened vials, manufactured under conditions that fell far short of sterile standards. The resulting meningitis outbreak killed dozens of people and sickened hundreds more.
More recently, compounded versions of GLP-1 weight loss drugs (the same class as Ozempic and Wegovy) have drawn FDA attention. The agency has received reports of adverse events tied to incorrect dosing in compounded versions. Some compounders used salt forms of the active ingredient that haven’t been reviewed or approved by the FDA, raising questions about whether those formulations behave the same way in the body.
The GLP-1 Compounding Situation
The surge in demand for GLP-1 weight loss and diabetes drugs created widespread shortages, which opened a legal window for pharmacies to compound versions of these medications. Under federal law, compounders can prepare copies of FDA-approved drugs when those drugs appear on the official shortage list.
As supply began to stabilize, the FDA announced transition periods. For semaglutide (the active ingredient in Ozempic and Wegovy), traditional pharmacies had until April 2025 and outsourcing facilities had until May 2025 to wind down compounding. For tirzepatide (the active ingredient in Mounjaro and Zepbound), the deadlines were earlier, in February and March 2025, though ongoing litigation has introduced some uncertainty about enforcement timing.
If you’ve been using a compounded version of one of these drugs, the key thing to understand is that once the shortage officially ends and the transition period expires, compounding pharmacies lose their legal basis to keep making copies of the commercially available product.
Cost and Insurance Coverage
Insurance coverage for compounded drugs is inconsistent. Many insurance plans don’t cover them, and even plans that do may impose significant out-of-pocket costs depending on the drug’s tier placement, your deductible, and your plan’s benefit structure. Coverage decisions are made by individual payers, and FDA approval of a drug doesn’t automatically guarantee that any insurer will reimburse it, let alone a compounded version that lacks FDA approval entirely.
In practice, many patients pay out of pocket for compounded medications. Costs vary widely depending on the ingredients, the complexity of preparation, and whether the drug requires sterile compounding (which is more labor-intensive and expensive). For some patients, a compounded drug is actually cheaper than the brand-name alternative, which is part of what drove demand for compounded GLP-1 drugs costing a fraction of the $1,000-plus monthly price of the commercial versions. For others, especially when insurance would have covered an approved alternative, compounding can be the more expensive route.
What to Look for in a Compounding Pharmacy
If you’re prescribed a compounded medication, the pharmacy matters. Look for accreditation from the Pharmacy Compounding Accreditation Board (PCAB), which verifies that a pharmacy meets quality and safety standards beyond the legal minimum. Check whether the pharmacy is licensed in your state and whether it has any recent disciplinary actions on record with the state board of pharmacy.
For sterile compounded drugs, the stakes are higher. Ask whether the pharmacy follows USP sterile compounding standards, whether it conducts potency testing on finished products, and how it monitors its clean room environment. A reputable compounding pharmacy will be transparent about its processes and willing to answer these questions directly.