Dose suggestions for C. johimbe bark vary widely and it would be wise to establish individual tolerance before trying high doses. Some suggest using 2-4g (Torsten pers. comm.), though Miller (1985) suggested 30g! I suspect this latter figure may be due to the use of low-quality bark. Bark shavings are prepared non-traditionally by bringing 2 cups of water to a boil, reducing to a simmer, adding the juice from 1⁄4 of a lemon or lime [see Citrus] or c.1g ascorbic acid, and then adding the powdered root bark and simmering for a further 10 minutes. This brew is then filtered through coffee-filter papers while still hot, then cooled to room temperature for consumption. The material may be more effectively extracted by soaking in alcohol for c.8 hours, before straining and evaporating the alcohol to leave a crude alkaloidal residue. The purpose of adding a source of vitamin C is to increase the absorption of yohimbine and other alkaloids, as well as reducing the time to onset of effects. The tea is quite bitter, and ascorbic acid also reduces the likelihood of nausea. It is reported to be best consumed as quickly as possible. Effects of plain tea may be felt in 30-60 minutes; the alcohol extract in 10-20 minutes. Effects include warm tingles up the spine, relaxation of limbs, hypertension, mental stimulation, mild perceptual alterations in higher doses, and often a spontaneous erection lasting several hours, due to stimulation of the spinal ganglia which control penile erectile tissue. Lower doses of yohimbine are more effective for sexual purposes than higher doses. When used as a sexual tonic, 250-500mg may be taken every morning after food. Due to yohimbine’s MAOI activity, it should not be taken with amphetamines or tyramine-rich foods; also should not be taken by those with kidney, liver or heart problems, or by diabetics or hypoglycaemics. Combined with tricyclic antidepressants, dangerous hypertension may result (Crenshaw & Goldberg 1996; Fugh-Berman 2000; Miller 1985; Rätsch 1992; Torsten pers. comm.). Yohimbe can also interact dangerously with dextromethorphan [DXM] (pers. comm.).
It is suggested that blood-sugar levels be kept high when consuming yohimbe, to reduce the incidence of unpleasant reactions. Drinking a glass of milk immediately before consumption has also been suggested to minimise unwanted side-effects (Torsten pers. comm.). Chocolate [see Theobroma] should not be consumed, even with small doses of yohimbe. Ginseng [see Panax] also interacts with yohimbe so that only 1⁄4 of the usual yohimbe dose may be needed for the same level of effect (theobromus pers. comm.).

P. ginseng is anxiolytic; stimulates the immune system; regulates the CNS; relieves fatigue; enhances memory, learning, alertness and other cognitive functions; increases cerebral circulation; prevents or compensates for damage to the nervous and endocrine systems caused by stress; inhibits uptake of dopamine, GABA, glutamate, norepinephrine and serotonin in rat brain; increases rate of alcohol metabolism; acts as an aphrodisiac; stimulates liver function, including synthesis of RNA, DNA and vital proteins; strengthens the heart; helps prevent and heal stomach ulcers; balances hormone activity, protects and stimulates adrenal function; counteracts intoxication, and helps relieve hangover; is an antioxidant and free-radical scavenger; helps heal deformities of the cornea, especially clouding; regulates blood-sugar, blood pressure, and red and white blood-cell count according to the body’s need; and shows some antitumour and anticancer activity in humans. It should not be combined with the pharmaceutical drug phenelzine, as headaches and tremor may result.

An In vitro study assessing the interactions of ginsenosides found that Panax Ginseng was able to reduce the catalytic activity of CYP1A1 and CYP1A2 (two variants of Aromatase) and CYP1B1 in a dose-dependent manner that correlated with Ginsenoside content.[45] The inhibition appeared to be competitive for CYP1A1 and mixed for the other two, with CYP1A2 being more susceptable