Formulary
Tryptophan: Indications, Dosing, Side Effects and Interactions
Tryptophan is an essential dietary amino acid, and is a precursor of serotonin; it re-establishes the inhibitory action of serotonin on the amygdaloid nuclei,...
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Tryptophan: Indications, Dosing, Side Effects and Interactions
Tryptophan is an essential dietary amino acid, and is a precursor of serotonin; it re-establishes the inhibitory action of serotonin on the amygdaloid nuclei,...
Drug action
Tryptophan is an essential dietary amino acid, and is a precursor of serotonin; it re-establishes the inhibitory action of serotonin on the amygdaloid nuclei, thereby reducing feelings of anxiety and depression.
Indications and dose
**Treatment-resistant depression (used alone or as adjunct to other antidepressant drugs) (initiated under direction of hospital consultant)**
- **Adult** (By Mouth): 1 g 3 times a day; maximum 6 g per day.
Contraindications
History of eosinophilia myalgia syndrome following use of tryptophan
Side effects
Frequency not known Asthenia; dizziness; drowsiness; eosinophilia myalgia syndrome; headache; myalgia; myopathy; nausea; oedema; suicidal behaviours Side-effects, further information If patients experience any symptoms of eosinophilia myalgia syndrome (EMS), manufacturer advises to withhold treatment until possibility of EMS is excluded.
Interactions
**Other interactions (5):**
- Serotonergic medications Serotonin is formed from dietary tryptophan and stored in the presynaptic terminal.
- John's Wort [ Hypericum perforatum ], opioids [e.g., fentanyl and its analogues, tramadol, dextromethorphan, tapentadol, pethidine, methadone, pentazocine, buprenorphine and buprenorphine/naloxone...
- The concomitant use of venlafaxine with serotonin precursors (such as tryptophan supplements) is not recommended (see section 4.4).
- However, lithium (and possibly also tryptophan) enhances the serotonergic effects of fluvoxamine.
- Serotonergic drugs (lithium, tramadol, triptans, tryptophan, selegiline (MAOI-B), St.
Pregnancy
Manufacturer advises caution-no information available.
Breast feeding
Manufacturer advises avoid-no information available.
Medicinal forms
Capsule
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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