Active placebo

Nomenclature

According to a 1965 paper, the term "concealed placebo" (German: Kaschiertes Placebo) was suggested in a 1959 paper published in German.

Example

An example of an active placebo is the 1964 work of Shader and colleagues who used a combination of low-dose phenobarbital plus atropine to mimic the sedation and dry mouth produced by phenothiazines.

Morphine and gabapentin are painkillers with the common side effects of sleepiness and dizziness. In a 2005 study assessing the effects of these painkillers on neuropathic pain, lorazepam was chosen as an active placebo because it is not a painkiller but it does cause sleepiness and can cause dizziness.

Testing from the late 1950s onwards on narcotic analgesics like morphine also has used dicyclomine as an active placebo, and on some occasions it was reported to cause the Straub mouse tail reaction, as do most narcotics. Clonidine is now finding more use as an active placebo for narcotics.

References

References

1. (April 1965). "Nonblind placebo trial: an exploration of neurotic patients' responses to placebo when its inert content is disclosed". Archives of General Psychiatry.
2. (1959). "Das Placeboproblem". Fortschr Arzneimittelforsch.
3. (March 31, 2005). "Morphine, gabapentin, or their combination for neuropathic pain". [[N Engl J Med]].