Recently, a study conducted by Oregon State University has found that blood samples collected from blood bank donors which are labeled as “pure” contain traces of caffeine, cold medicine, and anti-anxiety medicine.
The researchers tested 18 batches of human blood serum and found that each of them contained caffeine. Concerns over caffeine are small, but the researchers were alarmed to find other prescription medicines and some over-the-counter cough medicines in the samples.
Eight samples contained an over-the-counter cough suppressant medicine (dexmethorphan), and thirteen out of eighteen samples contained alprazolam—which you may know as Xanax, a prescription medication used to treat anxiety.
Due to the small sample size of this study, it is impossible to know how far-reaching the consequences of not having “clean” blood samples go. Since all of the samples contained caffeine, it is a reminder of how commonplace this nootropic has become, but it’s also important to look at it from the perspective of needing blood samples that do not contain caffeine. The contamination of caffeine in the blood samples may not pose a problem for a healthy individual with no possibility of drug interactions, but if you take medications which may interact adversely with caffeine, it could definitely cause unwanted effects. Similarly, the contamination of Xanax could interact with other medications the patient needing a transfusion may be taking.
The study wants to remind us that they only used a chemical assay screening process which had to look for specific medications for which it was programmed. The scientists are opening up the discussion for what other medications might be in the blood– for which they haven’t routinely been tested.
Chen, Luying, and Richard B.van Breemen. “Validation of a Sensitive UHPLC-MS/MS Method for Cytochrome P450 Probe Substrates Caffeine, Tolbutamide, Dextromethorphan, and Alprazolam in Human Serum Reveals Drug Contamination of Serum Used for Research.” Journal of Pharmaceutical and Biomedical Analysis, vol. 179, 5 Feb. 2020, doi:https://doi.org/10.1016/j.jpba.2019.112983.