A purity percentage is not a complete description of a medication. It leaves separate questions about the amount of active ingredient, contamination, labeling, storage and whether the product is appropriate for human use.

FDA identifies contamination and too much or too little active ingredient as serious risks when compounded drugs are not prepared to appropriate standards. Those are different problems that a single advertised percentage cannot resolve.[1][2]

Read what the report identifies

A laboratory report concerns the sample and tests named on that report. To understand its relevance to a vial being sold, the seller would need to explain how the report connects to that particular product and batch.

The useful details are concrete: the laboratory, the date, the sample identity, the measurements performed and the batch identifier. If those details are absent, the percentage alone gives little information about the vial a person would receive.

It also does not explain the clinical evidence for the intended use. A product can be described chemically without establishing a health benefit.

Check the dispensing source separately

FDA recommends that an online pharmacy require a prescription, be licensed by a state board of pharmacy, provide a U.S. physical address and have a licensed pharmacist available for questions.[3]

These checks identify an accountable dispensing source. A downloadable report or a description such as “research grade” does not replace them.

A price comparison becomes meaningful only after the product and source are clear. Two listings with similar ingredient names may still differ in formulation, concentration, labeling and the services attached to the order.

Compounding has its own status

A compounded prescription is not an FDA-approved generic. Compounded drugs are not FDA-approved, and FDA does not review their safety, effectiveness or quality before marketing. They may serve particular medical needs when an approved drug is not appropriate.[2]

The evidence should describe the actual preparation, and the prescription should have a clear medical reason.