Table 4. Tyramine-Containing Foodsa continued...
Foods that contain large amounts of tyramine, such as cheese, chicken liver, chocolate, beer, and wine, may provoke hypertension (initially manifesting as headache) and cardiac dysrhythmias.
St. John's wort
There continue to be high levels of enthusiasm for the use of herbs and dietary supplements for controlling symptoms and improving health-related quality of life and well-being. One popular herbal agent that has been used to treat depression is St. John's wort, a plant with Greek origins. The major active constituents in St. John's wort are hypothesized to be melatonin, hypericin, hyperforin, and adhyperforin, although hypericin may not reach sufficient concentrations in humans to have biologic activity. Hypericin is thought to be a monoamine oxidase inhibitor, while hyperforin and adhyperforin are believed to inhibit the reuptake of serotonin, dopamine, and norepinephrine.[48,49,50,51] These mechanisms of action provide the rationale for evaluating St. John's wort for depression management.
During the last 25 years, many trials have compared St. John's wort to placebo, to antidepressants, and sometimes to both placebo and antidepressants. A wide range of results have emerged, from finding no differences between arms, to finding St. John's wort improving outcomes over placebo for moderate depression, to finding St. John's wort preferable to placebo in general, to finding St. John's wort equal to antidepressants in alleviating depressive symptoms.;[53,54][Level of evidence: I] Older studies comparing St. John's wort to antidepressant therapy tended to use low doses of antidepressants and did not titrate up by response to the usual doses used for managing depression. The best overview of the research in this area is provided in a meta-analysis of randomized controlled trials. Conclusions from this meta-analysis, which includes 37 trials, are that St. John's wort does not have a clinically important effect on major depressive disorder and that for milder depression, it may have some effect (but it is not large).
Side effects reported in studies of St. John's wort are minimal. One study that compared St. John's wort to sertraline and placebo found that the side effects of St. John's wort that were significantly different from those of placebo included anorgasm, frequent urination, and swelling.[Level of evidence: I] A meta-analysis of randomized controlled trials found that fewer patients withdrew from trials because of adverse effects from St. John's wort, compared with antidepressants.