Inert substances do not exist, and no norms exist for what a placebo must consist of. This, of course, affects the results of the studies.
There is no requirement to disclose the contents of placebo used in clinical trials. Medical journals do not require this information either.
The authors analysed 167 clinical studies, published in four of the most prestigious medical journals. Most of the clinical studies did not disclose the composition of the placebo. Only studies for 8% of pills and 26% of injections reported what was used as the placebo. For example, in the study on medication for anorexia associated with cancer, it was found that the medication positively affects the GIT. However, lactose was used as the placebo. Oncological patients who are undergoing chemo and radiation therapy usually have lactose intolerance, which resulted in the medication which did not contain lactose differing favorably from the “placebo”.
In 1930, two doctors from the German city of Lübeck decided to vaccinate children en masse against tuberculosis with the BCG vaccine which, although it had been available since 1921, had not really been used. In the 12 months of this campaign, 208 children contracted tuberculosis due to the vaccinations, and 77 died. The doctors were arrested and convicted of murder.
This led to discussion on the use of children in medical experiments. In 2008, the USA renounced the Declaration of Helsinki. (Instead, it uses Good Clinical Practice, which does not restrict pharmaceutical companies as much as the Declaration of Helsinki).
In vaccine studies it is possible to use saline (an isotonic solution), but researchers often choose other medicines. The article cites four examples:
In the study on a vaccine for pneumococcus (PCV9), another vaccine (DTP-Hib) was used as the placebo.
In the study on a vaccine for cholera, a vaccine for E. coli was used as the placebo.
In another study on a vaccine for pneumococcus (PCV23), vaccines for hepatitis A and B were used.
In a fourth study, aluminium hydroxide mixed with thiomersal (ethylmercury) was used as the placebo.