St Johns Wort and Ethiopian herbs
Travelling in the Ethiopian highlands, through the Simien Mountains, I was amazed to see so many so-called Mediterranean herbs growing wild. We walked across meadows of fragrant thyme, grazed by goats and sheep. The meat from these animals is highly prized and flavourful, like our saltbush–fed lamb in Australia.
From thyme meadows we walked into a forest of Hypericum trees (St John’s wort). This herb rarely gets above bush-sized in Mediterranean climates. Then in the higher meadows, the fennel (in flower) was man-height, and roses grew wild and tall. Aloe species were in flower, teetering on the edge of cliffs. Violets, valerian and marsh mallows grew green and lush in the shady areas, under trees hung with moss and air-ferns.
I did wild-harvest some St John’s wort flowers and add these to my tea, to celebrate walking through a forest of it. Plant material can’t be brought back into Australia, so I’ve just brought back pictures and information on the use of SJW, a primary herb for treatment of depression and menopause symptoms.
Evidence for the effectiveness of SJW in treating depression
A number of good quality clinical trials using St John’s wort (Hypericum perforatum) extracts (SJW) have shown it to be effective in treating both moderate depression and major depressive disorders. SJW was as effective as selective serotonin re-uptake inhibitors (SSRI’s) and had fewer side effects.
SJW and SSRIs change moods and serotonin levels in the brain
Since SJW binds to the same receptors as SSRIs, SJW increases the effects of these drugs when they are taken together. SSRI and SJW both prolong serotonin’s effects in the brain, improving moods and stabilising mood swings. Thus SJW is widely used to treat mild depression and the mood swings experienced due to hormonal fluctuations in menopause. However, taking SSRI plus SJW can result in serotonin overdose, causing skin flushes/rash, allergic responses, fluid retention, agitation and nausea.
Combined use of SJW and SSRIs poses a risk, with readily available SJW often bought over the counter. Both medical and herbal practitioners need to be well aware of this risk and to inform their patients of additive effects. Patients also need to fully inform their doctors of any herbal medicine that they have bought over the counter.
SJW and drug interactions: the bad news
SJW extracts contain more than 27 phytochemicals, including hypericin and hyperforin. SJW with high levels of hyperforin (5% or more) can cause rapid clearance of many drugs from the blood, resulting in decreased effectiveness of these drugs. Hyperforin induces the expression biochemical cytochromes responsible for clearance of up to 50% of known drugs via the liver. This includes drugs used to treat heart disease (digoxin), cholesterol-lowering statins and immunosuppressive drugs such as cyclosporine (see Research pages and Buttermick 2009, for a table listing interaction).
Low Hyperforin SJW is effective : the good news!
When high and low hypeforin preparations were compared in trials treating depression, the low hyperforin, high hypericin preparations were effective, and did not interact with processing of other drugs. They still changed serotonin levels to the same extent as the high hyperforin preparations. The preparation marketed as Remotiv by Flordis here in Australia, as a practitioner-only product, has very low amounts of hyperforin (0.2%)
“Three clinical trials performed using this SJW extract showed that it was superior to placebo and as effective as SSRIs imipramine and fluoxetine, thus showing that hyperforin is not needed for the anti-depressive efficacy of SJW. No drug interaction has been reported with products that have low contents of hyperforin.”
From, “St. John’s Wort: Quality Issues and Active Compounds”, Veronika Butterweck, 539-40370_ch01_3P.indd, 2009 in Botanical Medicine: From Bench to Bedside, Chapter 4, pp 69-91, Edited by R. Cooper and F. Kronenberg. See Research pages,