The researchers found when they controlled for multiple comparisons, both the standard dose (0.5 mg/kg) and the high dose (1 mg/kg) of IV ketamine were superior to
active placebo. The low dose (0.1 mg/kg) was significant only prior to adjustment (P = 0.02; P-adjusted = 0.14).
"So with a lower dose of MDMA in the
active placebo, it might fool the subject or the therapist.
To account for that possibility, he said some researchers are using more
active placebos such as midazolam, but he did not think that it was a complete solution because the ideal
active placebo would affect glutamate, dopamine, and noradrenaline without having an antidepressant effect.
Limitations of the study included the use of an
active placebo (although with no noted CNS effects), the allocation of all moderate-severely anxious individuals into one group and a short wash-out period with potential carryover effect of the herb.
Led by Dan Iosifescu, MD, Associate Professor of Psychiatry at Mount Sinai; Sanjay Mathew, MD, Associate Professor of Psychiatry at Baylor College of Medicine; and James Murrough, MD Assistant Professor of Psychiatry at Mount Sinai, the research team evaluated 72 people with treatment-resistant depression-meaning their depression has failed to respond to two or more medications-who were administered a single intravenous infusion of ketamine for 40 minutes or an
active placebo of midazolam, another type of anesthetic without antidepressant properties.
You could call antidepressants an
active placebo because they are real, they are potent, and they have very long lists of adverse effects.
Participants were randomly selected to receive different combinations of vitamin C, vitamin E and a non
active placebo.