How to read a certificate of analysis in under two minutes

A certificate of analysis (COA) is a laboratory's report on a specific sample from a specific lot. It is not a general statement that a pharmacy's products are good; it is evidence about one batch. That makes it useful — and it means the first thing to check is whether it is evidence about the right batch.

1. Match the lot

Find the lot number on the COA and compare it with the lot number on the label your patient received. Then check the preparation name, the strength and the dosage form. A COA for testosterone cypionate 200 mg/mL tells you nothing about a 250 mg/mL lot.

2. Check who did the testing

Look for the laboratory's name, address and an authorizing signature with a date. An independent lab is a stronger check than in-house testing. Many reputable labs hold ISO/IEC 17025 accreditation, the international standard for testing laboratories; it is often noted on the report.

3. Read potency against its specification

Potency is usually reported as a percentage of label claim — for example, 99.4%. What matters is whether the result falls inside the acceptance range listed beside it (the specification). Note the method too; high-performance liquid chromatography (HPLC) is the most common for hormones and peptides. A result with no stated specification is hard to interpret.

4. For sterile preparations: sterility

Sterility testing, typically following USP <71>, incubates samples to see whether anything grows. The result you want is a clear pass or "no growth." Because incubation takes around 14 days, check the dates: the test should have been completed before the lot shipped.

5. For sterile preparations: bacterial endotoxin

Endotoxins are fragments of bacterial cell walls that can cause fever and other reactions even when a product is sterile. Testing usually follows USP <85> and reports a value in endotoxin units per millilitre (EU/mL), such as < 0.5 EU/mL, compared with a limit. The limit depends on the drug, dose and route, so look for a stated limit and a pass.

6. Check the dates

Look at when the sample was received, when testing was completed, and how that relates to the compounding date and the beyond-use date on the label. Results that post-date shipment, or a COA that is older than the lot itself, are worth a phone call.

Ingredient COA vs finished-preparation COA

There are two kinds of COA in compounding, and both matter. The supplier COA describes the raw active ingredient as it arrived at the pharmacy. The finished-preparation COA describes the compounded product your patient actually receives. A clean ingredient COA does not prove the preparation was compounded correctly — only testing of the finished lot does that.

Every BioForm shipment includes the COA for the lot dispensed, and we are happy to send the most recent COA for any preparation before you prescribe. Just ask.