4.4. Ibogaine and Noribogaine
Ibogaine is an alkaloid substance obtained from the root bark of the shrub Tabernanthe iboga, endemic to Western African regions.88 It has been historically used by indigenous communities in West Africa for religious ceremonies, and also to treat fatigue.88 Its ceremonial use is due to itsoneirophrenic properties, which means it can invoke dream-like states without loss of consciousness.88 While preclinical studies of ibogaine and noribogaine have suggested that both ibogaine and noribogaine dose-dependently increase the antinociceptive properties of morphine, making it a potential opioid-sparing strategy in pain management, no human laboratory clinical trials have investigated the use of ibogaine for pain.
Convergent preclinical models have suggested that ibogaine could be used as a modulator of morphine antinociception.89,90Co-administration of ibogaine in various doses (1-40mg/kg) and morphine (4 mg/kg) increased morphine-induced antinociception in a dose-dependent manner for rats in a heat-pain paradigm. Further, the administration of 40mg/kg of noribogaine, the primary metabolite of ibogaine, resulted in similar effects. Ibogaine enhances the pain-relieving effects of morphine in mice. After making all mice tolerant to morphine, researchers compared two groups: one given morphine alone and the other with morphine and varying doses of ibogaine or noribogaine. Both ibogaine and noribogaine were found to increase morphine’s antinociception effects. To our knowledge, no studies have investigated whether patients receiving morphine could have analgesic effects maximized by ibogaine, thus reducing the total opioid requirement to alleviate pain.