Da Prada M, Zurcher G, Wuthrich I, Haefely WE. On tyramine, food, beverages and the reversible MAO inhibitor moclobemide. J Neural Transm Suppl 1988;26:31-56.
Abstract: The pathways for the biosynthesis and metabolism of tyramine are described as a basis for the discussion of the interaction between MAO inhibitors and tyramine. While a role of endogenous tyramine in the antidepressant action of MAO inhibitors remains purely hypothetical at this time, the mechanisms leading to the potentiation of the tyramine pressor effect ("cheese effect") are well known. Experiments in animals and man have provided concordant quantitative information on the effect of irreversible and some novel reversible MAO inhibitors on the presystemic disposition of orally ingested tyramine and on the noradrenaline-releasing action of tyramine in noradrenergic nerve terminals. There is a profound difference in the magnitude of tyramine potentiation between the irreversible inhibitor tranylcypromine and the reversible inhibitor moclobemide. A systematic analysis of the tyramine content of current European food and beverage is reported and serves as a rational basis for providing advice to patients on moclobemide. Most of the food and beverages analyzed contain less tyramine than previously reported and a few rules concerning rare cheeses with high tyramine content are sufficient to eliminate the risk of hypertensive crises.
Gardner DM, Shulman KI, Walker SE, Tailor SA. The making of a user friendly MAOI diet. J Clin Psychiatry 1996 Mar;57(3):99-104. (Review)
Abstract: BACKGROUND: Many monoamine oxidase inhibitor (MAOI) diets are considered to be excessively restrictive and founded on poor scientific evidence. We present a safe and practical MAOI diet based on the related clinical and analytic data. METHOD: We used a critical review of the literature and our own tyramine assay results to categorize foods to be restricted absolutely, taken in moderation only, or unrestricted. RESULTS: We recommend that users avoid aged cheese; aged or cured meats (e.g., air-dried sausage); any potentially spoiled meat, poultry, or fish; broad (fava) bean pods; Marmite concentrated yeast extract; sauerkraut; soy sauce and soy bean condiments; and tap beer. Wine and domestic bottled or canned beer are considered safe when consumed in moderation. Other foods not mentioned are considered unrestricted. CONCLUSION: The concerns about perpetuating an overly restrictive MAOI diet include the avoidance by prescribers of a potentially useful treatment option, excessive limitations on lifestyle for patients, and increased risk to patients secondary to noncompliance with the diet. We propose an MAOI diet that has a solid scientific and clinical basis and that is, above all, practical.
Goff DC. Two cases of hypomania following the addition of L-tryptophan to a monoamine oxidase inhibitor. Am J Psychiatry 1985 Dec;142(12):1487-1488.
Abstract: The combination of L-tryptophan and a monoamine oxidase inhibitor (MAOI) has been reported to be an effective antidepressant regimen. Neurotoxicity has previously been associated with this combination. The author presents two cases of hypomania following the addition of L-tryptophan to an MAOI.
Korn A, Da Prada M, Raffesberg W, Gasic S, Eichler HG. Effect of moclobemide, a new reversible monoamine oxidase inhibitor, on absorption and pressor effect of tyramine. J Cardiovasc Pharmacol 1988 Jan;11(1):17-23.
Abstract: We determined in healthy subjects the pressor effect and the plasma level of free tyramine in response to intravenous and oral tyramine doses before and after therapeutic doses (3 X 100 mg/day) of moclobemide, a new reversible, preferential type A monoamine oxidase (MAO) inhibitor. In fasting subjects moclobemide increased the pressor effect of intravenously and orally administered tyramine; the tyramine dose-pressor curve was shifted to the left by factors of 2.4 and 4.1, respectively. No increase in systolic blood pressure occurred at free plasma tyramine concentrations lower than 70 ng/ml before, and 20 ng/ml after, moclobemide. Peak plasma tyramine concentrations increased dose-dependently after oral tyramine; after moclobemide similar peak plasma concentrations of tyramine were obtained with 2.6 times smaller doses of tyramine. Thus, the potentiation by moclobemide of the pressor effect of oral tyramine appears to be due to inhibition of tyramine first-pass metabolism, as well as to inhibition of tyramine catabolism by MAO within adrenergic nerve terminals. The peak concentrations of free tyramine in plasma and the concomitant increase of systolic blood pressure were significantly (p less than 0.01) smaller when tyramine was administered with a meal (before or after moclobemide) than when given with tap water. We conclude that at doses of 3 X 100 mg/day moclobemide induces only a mild potentiation of the pressor effect of tyramine. This potentiation is virtually absent under natural conditions when tyramine is given with a meal.
Muller T, Gieschke R, Ziegler WH. Blood pressure response to tyramine-enriched meal before and during MAO-inhibition in man: influence of dosage regimen. J Neural Transm Suppl 1988;26:105-114.
Abstract: In an open study oral tyramine in variable doses was administered to six healthy volunteers under three different conditions: 1) without moclobemide, 2) under moclobemide steady-state conditions (3 X 200 mg moclobemide daily) one hour after moclobemide intake and 3) under moclobemide steady-state conditions simultaneously with moclobemide. It was shown that the amount of tyramine effecting 30-50 mmHg systolic blood pressure increase was roughly doubled when moclobemide was administered together with tyramine instead of one hour before tyramine intake. The time interval between tyramine ingestion and maximal blood pressure increase did not differ significantly between conditions 2) and 3). The conclusion of this study is that moclobemide should always be taken at the end of a meal, which is anyway the usual time for drug intake.
Pohl R, Balon R, Berchou R. Reaction to chicken nuggets in a patient taking an MAOI. Am J Psychiatry 1988 May;145(5):651. (Letter)
Pope HG Jr, Jonas JM, Hudson JI, Kafka MP. Toxic reactions to the combination of monoamine oxidase inhibitors and tryptophan. Am J Psychiatry 1985 Apr;142(4):491-492.
Abstract: The combination of monoamine oxidase inhibitors and tryptophan--a recognized antidepressant regimen--has been reported to cause behavioral or neurologic toxicity. The authors present eight cases of delirious syndromes apparently attributable to this combination of agents.
Rafaelsen OJ. Cheese effects and new reversible MAO A inhibitors: summary. J Neural Transm Suppl 1988;26:123-124
Shulman KI, Walker SE, MacKenzie S, Knowles S. Dietary restriction, tyramine, and the use of monoamine oxidase inhibitors. J Clin Psychopharmacol 1989 Dec;9(6):397-402.
Abstract: The aim of this study is to provide clearer guidelines for rational, safe, and practical dietary restriction for use with monoamine oxidase inhibitors. Tyramine levels were assayed in over 100 of the controversial foods that have been associated with hypertensive reactions or reported to contain high levels of tyramine. Only a very limited number of foods appear to require absolute restriction. These include all aged cheeses, concentrated yeast extracts (e.g., Marmite), sauerkraut, and broad bean pods. Alcoholic beverages, including Chianti wine consumed in moderation, appear to be safe. Some aged meats contain relatively high levels of tyramine and require closer investigation
Shulman KI, Tailor SA, Walker SE, Gardner DM. Tap (draft) beer and monoamine oxidase inhibitor dietary restrictions. Can J Psychiatry 1997 Apr;42(3):310-312.
Abstract: OBJECTIVE: Traditional monoamine oxidase inhibitors (MAOIs) continue to play an important role in the management of a wide variety of clinical conditions. Accordingly, a practical and safe approach to MAOI dietary restrictions remains an essential component of patient management. METHOD: In an effort to refine MAOI dietary recommendations, we report a case of hypertensive crisis following the consumption of a modest amount of tap beer. RESULTS: A well-documented case report involving tap (draft) beer consumed while on an MAOI supports an earlier study, which recommended that all tap beers be restricted on MAOI diets. The 2 cases were remarkably similar in terms of the offending substance, quantity consumed, and subsequent reaction. CONCLUSIONS: As a result of recent tyramine analyses and 2 well-documented case reports, all tap (draft) beers should now be absolutely restricted on MAOI diets because they represent a very significant risk at modest levels of consumption.
Sullivan EA, Shulman KI. Diet and monoamine oxidase inhibitors: a re-examination. Can J Psychiatry 1984 Dec;29(8):707-711. (Review)
Abstract: Monoamine oxidase inhibitors (MAOIs) are attracting renewed attention as effective antidepressants for refractory depressions, particularly among the elderly. However, widespread fears concerning the interactions of MAOIs with tyramine-containing foods have led to the development of long and complicated diets. These diets have served as an obstacle to the ready use of MAOIs, yet very little systematic or critical review of the basis for food restriction has been undertaken. An international survey of MAOI diets was conducted and from the diets collected, foods were categorized according to frequency of restriction on the diet lists. On the basis of this survey and a critical review of the literature it was determined that only four foods clearly warrant absolute prohibition: aged cheese, pickled fish (herring), concentrated yeast extracts and broad bean pods. While there is insufficient evidence to prohibit alcohol completely (even chianti wine) true moderation must apply. It is suggested that a radically simplified diet should be investigated on a prospective basis.
Thom, Dickson. Surviving the Nineties Coping With Food Intolerances. Portland, OR, 1992.
Walker SE, Shulman KI, Tailor SA, Gardner D. Tyramine content of previously restricted foods in monoamine oxidase inhibitor diets. J Clin Psychopharmacol 1996 Oct;16(5):383-388.
Abstract: Traditional monoamine oxidase inhibitors (MAOIs) remain an important class of drugs for a variety of psychiatric conditions, including depressive illnesses, anxiety, and eating disorders. It was the objective of this study to refine the MAOI diet by determining the tyramine content of a variety of untested and "controversial" foods that continue to appear on MAOI diet-restricted food lists. A secondary objective of the study was to evaluate the effect of freshness on the tyramine content of some foods. Fifty-one food samples were evaluated for tyramine content by liquid chromatography. Food samples included a selection of sausages, beverages, sliced meat products, including chicken liver, and some fruits, including raspberries, bananas, and banana peels. Foods that were found to have dangerously high concentrations of tyramine (> or = 6 mg/serving) included chicken liver aged 9 days (63.84 mg/30 g), air-dried sausage (7.56 g/30 g), soy sauce (0.941 mg/ml), and sauerkraut (7.75 mg/250 g). Of the foods analyzed in this study, only those with high tyramine content per serving should continue to be absolutely restricted. All other foods are either safe for consumption or safe in moderation. The data provided should be combined with the data from other similar analytical studies to develop a list of foods that should be absolutely restricted. A more accurate list of restricted foods may enhance patient dietary compliance.