Tryptophan MAOIs

MAOIs TRYPTOPHAN Risk of confusion and agitation Tryptophan is a precursor to a number of neurotransmitters including serotonin. MAOIs inhibit the breakdown of neurotransmitters Reduce dose of tryptophan... 

Increasing the concentration of 5-HT by substrate loading has also been reported to produce the 5-HT syndrome. Administration of tryptophan, the substrate amino acid for 5-HT synthesis, in conjunction with a MAOI produces the syndrome (38,53,66,77,94,95,101,108). This effect is potentiated by pre-... 

MAOIs, metoclopramide, phenytoin, sibutramine, smoking, St. John s wort, tramadol, linezolid, L-tryptophan. 

Warning to the patient - Warn all patients against eating foods with high tyramine or tryptophan content and for 2 weeks after discontinuing MAOIs. 

Uses Obesity Action Blocks uptake of norepinephrine, serotonin, dopamine Dose 10 mg/d PO, may to 5 mg after 4 wk Caution [C, -] w/ SSRIs, Li, dextromethorphan, opioids Contra MAOI w/in 14 d, uncontrolled HTN, arrhythmias Disp Caps SE HA, insomnia, xerostomia, constipation, rhinitis, tach, HTN Interactions T Risk of serotonin synd W/ dextromethorphan, ergots, fentanyl, Li, meperidine, MAOIs, naratriptan, pentazocine, rizatriptan, sumatriptan, SSRIs, tryptophan, zolmitriptan, St. John s wort effects W/ cimetidine, erythromycin, ketoconazole T CNS depression W/ EtOH EMS Use fentanyl w/ caution, may T risk of serotonin synd concurrent EtOH use can T CNS depression OD May cause tach, HTN, diaphoresis, HA, fever, agitation, muscle tremors, and Szs symptomatic and supportive... 

MAOIs have the most serious pharmacodynamic interactions of any antidepressant class. As discussed earlier, they can cause a hypertensive crisis and the serotonin syndrome. They potentiate the hypertensive effects of most sympathomimetic amines, as well as tyramine, which is the reason for the avoidance of over-the-counter preparations containing such agents, in addition to the tyramine-free diet ( 508, 509). The serotonin syndrome occurs most often when MAOIs are used in combination with SSRIs and venlafaxine but it can also occur when MAOIs are used with tryptophan, 5-hydroxytryptophan, and some narcotic analgesics. In addition, MAOIs can also significantly potentiate the sedative and respiratory depressant effects of narcotic analgesics. 

Tryptophan Tryptophan interacts with MAOIs affecting phenothiazines and benzodiazepines. 

TRYPTOPHAN ANTICANCER AND IMMUNOMODULATING DRUGS-PROCARBAZINE Risk of hyperreflexia, shivering, hyperventilation, hyperthermia, mania or hypomania, disorientation/confusion Tryptophan is a precursor of a number of neurotransmitters, including serotonin. Procarbazine has MAOI activity, which inhibits the breakdown of neurotransmitters Tryptophan should be started under specialist supervision. Recommended to start with low doses and titrate the dose upwards with close monitoring of mental status and BP... 

Many reports have linked childhood hyperactivity to impaired central serotonin functions.89 In animals, the occurrence of a behavioral syndrome consisting of hyperactivity, stereotyped movements, and increase of temperature has been induced by L-tryptophan, as a serotonin precursor, by serotonin reuptake inhibitors, and by MAOIs.90 Most of these manifestations can be blocked specifically by pretreatment with an inhibitor of serotonin synthesis. In humans, the association of myoclonus, diarrhea, confusion, hypomania, agitation, hyperreflexia, shivering, incoordination, fever, and diaphoresis, when patients are treated with serotoninergic agents, could constitute a "serotonin syndrome." Such cases of serotonin syndrome were reported after treatments with L-tryptophan, MAOIs, serotonin reuptake inhibitors, and tricyclics, alone or in association. 

Hartmann, E., Chung, R., and Chien, C. P., Tryptophan and an MAOI(N-nialamide) in the treatment of depression. A double-blind study, bit. Pharma-... 

Following the first report of this syndrome, many other cases have been described involving tryptophan and MAOIs ,(p. 1151), the tricyclic antidepressants and MAOIs , (p.ll49), and, more recently, the SSRIs , (p.ll42) but other serotonergic drugs have also been involved and the list continues to grow. 

Because sibutramine inhibits serotonin uptake, and because the serious serotonin syndrome has been seen when serotonergic drugs were taken with SSRIs, the manufacturers say that sibutramine should not be taken with any serotonergic drugs. They name dextromethorphan, dihydroergot-amine, fentanyl, pentazocine, pethidine (meperidine), SSRIs, sumatriptan, and tryptophan. Possible cases have been reported for sibutramine and SSMs , (below).The US manufacturers also include lithium in their list. Note that this list is not exhaustive (see MAOIs under (d) above) and a case of the serotonin syndrome has been seen when venla-faxine was given with sibutramine. ... 

There appear to be no other reports suggesting that the combination of MAOIs and lithium is unsafe. However, there are a few reports of patients taking MAOIs and lithium who developed hyperpyrexia when given tryptophan , (p.ll51). The role (if any) of lithium in these cases is unknown. Note that lithium has been used to augment antidepressants although most of the data relate to trieyelies or SSRIs. Bear these cases in mind in the event of any unexpected response to treatment with MAOIs and lithium. 

Not understood. The reactions appear to be related to the serotonin syndrome, which can occur with two or more serotonergic drugs (see The serotonin syndrome , (p.9)). MAOIs may inhibit the metabolism of 5-hydroxytryptamine (serotonin), formed from tryptophan, so resulting in its accumulation. ... 

Information seems to be confined to the reports listed. Concurrent use can be effective in the treatment of depression, but occasionally and unpre-dictably severe and even life-threatening toxicity occurs. The authors of one of the reports detailed above recommend that patients on MAOIs should be started on a low dose of tryptophan (0.5 g). This should be gradually increased while monitoring the mental status of the patient for... 

The manufacturers of duloxetine contraindicate the concurrent use of MAOIs because of the theoretical risk of the serotonin syndrome. Similarly they recommend caution with other serotonergic drugs, including the SSRIs, venlafaxine, and tryptophan. Fluvoxamine should not be used with duloxetine, because it markedly increases duloxetine levels. Low-dose paroxetine caused a modest increase in the duloxetine ATJC, and fluoxetine is predicted to interact similarly. 

HT (bufotenine) have not been reliably detected in the brain under physiological conditons. They may possibly be formed when tryptophan is given together with a monoamine oxidase inhibitor (MAOI). 

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