Individuals not taking MAOIs may consume at least 2 grams of tyramine in a meal and not experience an increase in blood pressure, whereas those taking MAOIs such as tranylcypromine may experience a sharp increase in blood pressure following consumption of as little as 10 mg of tyramine, which can lead to hypertensive crisis.Foods containing tyramine include aged cheeses, cured meats, tofu and certain red wines. Some, such as yeast extracts, contain enough tyramine to be potentially fatal in a single serving. Spoiled food is also likely to contain dangerous levels of tyramine. Adverse effects
Incidence of adverse effectsVery common (>10% incidence) adverse effects include:

Dizziness secondary to orthostatic hypotension (17%)Common (1-10% incidence) adverse effects include:

Tachycardia (5–10%)
Hypomania (7%)
Paresthesia (5%)
Weight loss (2%)
Confusion (2%)
Dry mouth (2%)
Sexual function disorders (2%)
Hypertension (1–2 hours after ingestion) (2%)
Rash (2%)
Urinary retention (2%)Other (unknown incidence) adverse effects include:

Increased/decreased appetite
Blood dyscrasias
Chest pain
Diarrhea
Edema
Hallucinations
Hyperreflexia
Insomnia
Jaundice
Leg cramps
Myalgia
Palpitations
Sensation of cold
Suicidal ideation
TremorOf note, there has not been found to be a correlation between sex and age below 65 regarding incidence of adverse effects.Tranylcypromine is not associated with weight gain and has a low risk for hepatotoxicity compared to the hydrazine MAOIs.It is generally recommended that MAOIs be discontinued prior to anesthesia; however, this creates a risk of recurrent depression. In a retrospective observational cohort study, patients on tranylcypromine undergoing general anesthesia had a lower incidence of intraoperative hypotension, while there was no difference between patients not taking an MAOI regarding intraoperative incidence of bradycardia, tachycardia, or hypertension.
Precisely because tranylcypromine was not, like isoniazid and iproniazid, a hydrazine derivative, its clinical interest increased enormously, as it was thought it might have a more acceptable therapeutic index than previous MAOIs.The drug was introduced by Smith, Kline and French in the United Kingdom in 1960, and approved in the United States in 1961. It was withdrawn from the market in February 1964 due to a number of patient deaths involving hypertensive crises with intracranial bleeding. However, it was reintroduced later that year with more limited indications and specific warnings of the risks. Research
Tranylcypromine is known to inhibit LSD1, an enzyme that selectively demethylates two lysines found on histone H3. Genes promoted downstream of LSD1 are involved in cancer cell growth and metastasis, and several tumor cells express high levels of LSD1. Tranylcypromine analogues with more potent and selective LSD1 inhibitory activity are being researched in the potential treatment of cancers.Tranylcypromine may have neuroprotective properties applicable to the treatment of Parkinsons disease, similar to the MAO-B inhibitors selegiline and rasagiline. As of 2017, only one clinical trial in Parkinsonian patients has been conducted, which found some improvement initially and only slight worsening of symptoms after a 1.5 year followup. See also
Tranylcypromine/trifluoperazine


== References ==