5-HTP and medications.
5-HTP is classified as a targeted supplement in the Distil database, evidence Grade C. The page below lists every medication we have explicitly assessed it against.
5-HTP is a direct precursor to serotonin, and the serotonin question runs through everything that follows, both the benefit and the risk. On mood the evidence is Grade C, meaning emerging rather than settled, and it holds only for people with diagnosed depression rather than for low mood generally. The Cochrane review of 5-HTP and tryptophan for depression found the direction favourable and rated its own evidence too weak to be conclusive, and Javelle's 2020 review reaches much the same place. The largest 5-HTP trial in our records is Truyens 2022, in 166 patients across thirteen hospitals at 100mg twice daily, and it found depression, anxiety and stress scores no different from placebo, though its patients had inflammatory bowel disease with fatigue rather than depression, which is why we hold the claim to the diagnosed group and no wider. On sleep the evidence is also Grade C, and we do not offer 5-HTP for a sleep goal: the two monotherapy trials we hold are small, one of them single-blinded with no placebo arm, and between them they leave the question open rather than answered. On appetite we do not offer it either, because the only trial we hold behind that effect used 900mg a day, roughly three times the dose anyone would take from a supplement. The usual range is 50 to 300mg. The interactions are the part that matters most, and they are firm rather than cautionary. Taken alongside an antidepressant that acts on serotonin (an SSRI, an SNRI, a tricyclic, mirtazapine, trazodone, vortioxetine or an MAOI), St John's wort, lithium, a triptan, or the opioid painkillers tramadol, tapentadol, pethidine, pentazocine, methadone or fentanyl, 5-HTP adds to serotonin activity the medicine is already raising, and the combination carries a real risk of serotonin syndrome, so we treat every one of those as do not combine rather than as something to monitor. Many more medicines carry the same warning in their UK prescribing information, among them bupropion, buspirone and reboxetine, the opioids codeine, dihydrocodeine, oxycodone and buprenorphine, ADHD medicines such as methylphenidate and atomoxetine, some antipsychotics, and the anti-sickness medicines metoclopramide and ondansetron, and new brands appear all the time, so our reports do not rely on a list: we only suggest 5-HTP to someone who tells us they take no prescription medicine, and we take it out again if they name one of these medicines in any other answer. Some medicines with the same risk are sold without a prescription, so check the ingredients of any painkiller, cough or cold medicine, antihistamine, sleep aid, migraine tablet or brain supplement, and do not take 5-HTP with one containing codeine or dihydrocodeine (such as co-codamol, Nurofen Plus or Paramol), dextromethorphan, chlorphenamine (Piriton), diphenhydramine (such as Nytol Original or Panadol Night), methylene blue, or a triptan. It also interacts with carbidopa. Anyone with a current or past eating disorder should avoid it, because its appetite-suppressing effect works against recovery. Many people who reach for 5-HTP are already taking a serotonergic medicine without thinking of it as one, so the prescription list is the first thing to check rather than the last.
Below are the 58 documented pairs we have explicitly assessed for 5-HTP: 58 red. The pairs cluster around 1 mechanism: Additive serotonergic activity. Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not listed here is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by medication, and the missing-item form at the bottom of the page routes any uncatalogued medication into our next curation pass.
Documented interactions
Last reviewed 13 September 2026. Each interaction below lists the evidence its assessment drew on: some rest on studies of the exact pair, others on mechanism evidence, where a citation may support one part of the reasoning rather than the exact combination. The evidence line on each entry says which.
Additive serotonergic activity
Red Does 5-HTP interact with Almotriptan?
5-HTP is turned into serotonin in the body, and almotriptan is a migraine medicine that acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with almotriptan; if you already take both, tell the prescriber who manages your almotriptan, and do not stop almotriptan on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Amitriptyline?
5-HTP is turned into serotonin in the body, and amitriptyline blocks the reuptake of serotonin about as strongly as that of noradrenaline, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with amitriptyline; if you already take both, tell the prescriber who manages your amitriptyline, and do not stop amitriptyline on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Aripiprazole?
5-HTP is turned into serotonin in the body, and aripiprazole is an antipsychotic whose UK product information records serotonin syndrome, especially alongside other serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with aripiprazole; if you already take both, tell the prescriber who manages your aripiprazole, and do not stop aripiprazole on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Atomoxetine?
5-HTP is turned into serotonin in the body, and atomoxetine is an ADHD medicine whose UK product information records serotonin syndrome when it was taken with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with atomoxetine; if you already take both, tell the prescriber who manages your atomoxetine, and do not stop atomoxetine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Buprenorphine?
5-HTP is turned into serotonin in the body, and buprenorphine is an opioid whose UK product information warns of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with buprenorphine; if you already take both, tell the prescriber who manages your buprenorphine, and do not stop buprenorphine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Bupropion?
5-HTP is turned into serotonin in the body, and bupropion is a medicine UK prescribing guidance lists as raising the risk of serotonin syndrome with tryptophan, the substance 5-HTP is made from, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with bupropion; if you already take both, tell the prescriber who manages your bupropion, and do not stop bupropion on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Buspirone?
5-HTP is turned into serotonin in the body, and buspirone is an anxiety medicine whose UK product information warns about using it with L-tryptophan, the substance 5-HTP is made from, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with buspirone; if you already take both, tell the prescriber who manages your buspirone, and do not stop buspirone on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Chlorphenamine maleate?
5-HTP is turned into serotonin in the body, and chlorphenamine, the antihistamine in Piriton, also blocks the reuptake of serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with chlorphenamine; if you already take both, tell your GP or pharmacist.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Citalopram?
5-HTP is the precursor your body uses to make serotonin. Combined with an SSRI like citalopram, it can cause serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Clomipramine?
5-HTP is turned into serotonin in the body, and clomipramine is the tricyclic that acts most strongly on serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with clomipramine; if you already take both, tell the prescriber who manages your clomipramine, and do not stop clomipramine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Co-codamol?
5-HTP is turned into serotonin in the body, and co-codamol contains codeine, an opioid whose UK product information warns of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with co-codamol; if you already take both, tell your GP or pharmacist, and do not stop a prescribed painkiller on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Co-dydramol (Dihydrocodeine/paracetamol)?
5-HTP is turned into serotonin in the body, and co-dydramol contains dihydrocodeine, an opioid whose UK product information warns of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with co-dydramol; if you already take both, tell your GP or pharmacist, and do not stop a prescribed painkiller on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Codeine phosphate?
5-HTP is turned into serotonin in the body, and codeine is an opioid painkiller whose UK product information warns of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with codeine; if you already take both, tell your GP or pharmacist, and do not stop a prescribed painkiller on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Dexamfetamine sulfate?
5-HTP is turned into serotonin in the body, and dexamfetamine is a stimulant UK prescribing guidance lists as raising the risk of serotonin syndrome with tryptophan, the substance 5-HTP is made from, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with dexamfetamine; if you already take both, tell the prescriber who manages your dexamfetamine, and do not stop dexamfetamine on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Dihydrocodeine tartrate?
5-HTP is turned into serotonin in the body, and dihydrocodeine is an opioid painkiller whose UK product information warns of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with dihydrocodeine; if you already take both, tell your GP or pharmacist, and do not stop a prescribed painkiller on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Diphenhydramine hydrochloride?
5-HTP is turned into serotonin in the body, and diphenhydramine, the antihistamine in sleep aids such as Nytol Original and in some cough and cold medicines, also blocks the reuptake of serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with diphenhydramine; if you already take both, tell your GP or pharmacist.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Dosulepin?
5-HTP is turned into serotonin in the body, and dosulepin is a tricyclic antidepressant that also raises serotonin activity, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with dosulepin; if you already take both, tell the prescriber who manages your dosulepin, and do not stop dosulepin on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Doxepin?
5-HTP is turned into serotonin in the body, and doxepin is a tricyclic antidepressant that can add to serotonin activity, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with doxepin; if you already take both, tell the prescriber who manages your doxepin, and do not stop doxepin on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Duloxetine hydrochloride?
5-HTP raises serotonin levels. Combined with an SNRI like duloxetine, it can cause serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Eletriptan?
5-HTP is turned into serotonin in the body, and eletriptan is a migraine medicine that acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with eletriptan; if you already take both, tell the prescriber who manages your eletriptan, and do not stop eletriptan on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Escitalopram?
5-HTP raises serotonin levels. Combined with an SSRI like escitalopram, it can cause serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Fentanyl?
5-HTP is turned into serotonin in the body, and fentanyl is an opioid that has been involved in serotonin syndrome alongside serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with fentanyl; if you already take both, tell the prescriber who manages your fentanyl, and do not stop fentanyl on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Fluoxetine hydrochloride?
5-HTP is the precursor your body uses to make serotonin. Combined with an SSRI like fluoxetine, it can cause serotonin syndrome (agitation, sweating, tremor, confusion). Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Fluvoxamine?
5-HTP is the precursor your body uses to make serotonin. Combined with an SSRI like fluvoxamine, it can cause serotonin syndrome (agitation, sweating, tremor, confusion). Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Frovatriptan?
5-HTP is turned into serotonin in the body, and frovatriptan is a migraine medicine that acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with frovatriptan; if you already take both, tell the prescriber who manages your frovatriptan, and do not stop frovatriptan on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Imipramine?
5-HTP is turned into serotonin in the body, and imipramine is a tricyclic antidepressant that raises serotonin activity, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with imipramine; if you already take both, tell the prescriber who manages your imipramine, and do not stop imipramine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Isocarboxazid?
5-HTP raises serotonin levels. Combined with an MAOI like isocarboxazid, this can produce severe serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Linezolid?
5-HTP is the precursor your body uses to make serotonin, and linezolid is an antibiotic that also acts as an MAOI, blocking serotonin breakdown. Combining them can drive serotonin to dangerous levels, a reaction called serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Lisdexamfetamine dimesylate?
5-HTP is turned into serotonin in the body, and lisdexamfetamine is a stimulant UK prescribing guidance lists as raising the risk of serotonin syndrome with tryptophan, the substance 5-HTP is made from, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with lisdexamfetamine; if you already take both, tell the prescriber who manages your lisdexamfetamine, and do not stop lisdexamfetamine on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Lithium carbonate?
5-HTP is turned into serotonin in the body, and lithium increases serotonin activity in the brain, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with lithium; if you already take both, tell the prescriber who manages your lithium, and do not stop lithium on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Lofepramine?
5-HTP is turned into serotonin in the body, and lofepramine is a tricyclic antidepressant that strengthens serotonin signalling, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with lofepramine; if you already take both, tell the prescriber who manages your lofepramine, and do not stop lofepramine on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Lurasidone?
5-HTP is turned into serotonin in the body, and lurasidone is an antipsychotic whose UK product information warns of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with lurasidone; if you already take both, tell the prescriber who manages your lurasidone, and do not stop lurasidone on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Methadone hydrochloride?
5-HTP is turned into serotonin in the body, and methadone is an opioid that also blocks serotonin reuptake, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with methadone; if you already take both, tell the prescriber who manages your methadone, and do not stop methadone on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Methylphenidate hydrochloride?
5-HTP is turned into serotonin in the body, and methylphenidate is an ADHD medicine whose UK product information records serotonin syndrome when it was taken with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with methylphenidate; if you already take both, tell the prescriber who manages your methylphenidate, and do not stop methylphenidate on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Metoclopramide hydrochloride?
5-HTP is turned into serotonin in the body, and metoclopramide is an anti-sickness medicine whose UK product information warns that it can raise the risk of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with metoclopramide; if you already take both, tell the prescriber who manages your metoclopramide, and do not stop metoclopramide on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Mianserin?
5-HTP is turned into serotonin in the body, and mianserin is an antidepressant whose UK product information lists serotonin toxicity among the effects of too much of it, especially alongside other drugs that raise serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with mianserin; if you already take both, tell the prescriber who manages your mianserin, and do not stop mianserin on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Mirtazapine?
5-HTP is turned into serotonin in the body, and mirtazapine acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with mirtazapine; if you already take both, tell the prescriber who manages your mirtazapine, and do not stop mirtazapine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Moclobemide?
5-HTP is the precursor your body uses to make serotonin, and moclobemide is an MAOI (the reversible kind) that blocks serotonin breakdown. Combining them can drive serotonin to dangerous levels, a reaction called serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Naratriptan?
5-HTP is turned into serotonin in the body, and naratriptan is a migraine medicine that acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with naratriptan; if you already take both, tell the prescriber who manages your naratriptan, and do not stop naratriptan on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Nortriptyline?
5-HTP is turned into serotonin in the body, and nortriptyline is a tricyclic antidepressant with a weaker but real effect on serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with nortriptyline; if you already take both, tell the prescriber who manages your nortriptyline, and do not stop nortriptyline on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Oxycodone hydrochloride?
5-HTP is turned into serotonin in the body, and oxycodone is an opioid whose UK product information warns of serotonin toxicity with serotonergic antidepressants, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with oxycodone; if you already take both, tell the prescriber who manages your oxycodone, and do not stop oxycodone on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Paroxetine hydrochloride?
5-HTP raises serotonin levels. Combined with an SSRI like paroxetine, it can cause serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Phenelzine?
5-HTP raises serotonin levels. Combined with an MAOI like phenelzine, which blocks serotonin breakdown, this can produce severe serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Quetiapine?
5-HTP is turned into serotonin in the body, and quetiapine is an antipsychotic whose UK product information warns of serotonin syndrome with serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with quetiapine; if you already take both, tell the prescriber who manages your quetiapine, and do not stop quetiapine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Rasagiline?
Taking 5-HTP with rasagiline (an MAO-B inhibitor used for Parkinson's) can push serotonin to dangerous levels, because there is less MAO available to break it down, so we treat this as a do-not-combine pair. The combination has caused serotonin syndrome in case reports with other MAO inhibitors.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Reboxetine?
5-HTP is turned into serotonin in the body, and reboxetine is an antidepressant whose UK product information records serotonin syndrome, alone and with other serotonergic medicines, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with reboxetine; if you already take both, tell the prescriber who manages your reboxetine, and do not stop reboxetine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Rizatriptan?
5-HTP is turned into serotonin in the body, and rizatriptan is a migraine medicine that acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with rizatriptan; if you already take both, tell the prescriber who manages your rizatriptan, and do not stop rizatriptan on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Selegiline?
Taking 5-HTP with selegiline (an MAO-B inhibitor used for Parkinson's) can push serotonin to dangerous levels, because there is less MAO available to break it down, so we treat this as a do-not-combine pair. The combination has caused serotonin syndrome in case reports with other MAO inhibitors.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Sertraline?
5-HTP is the precursor your body uses to make serotonin. Combined with an SSRI like sertraline, it can cause serotonin syndrome (agitation, sweating, tremor, confusion). Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Sumatriptan succinate?
5-HTP is turned into serotonin in the body, and sumatriptan is a migraine medicine that acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with sumatriptan; if you already take both, tell the prescriber who manages your sumatriptan, and do not stop sumatriptan on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Tramadol hydrochloride?
5-HTP is turned into serotonin in the body, and tramadol raises serotonin as part of how it works, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with tramadol; if you already take both, tell the prescriber who manages your tramadol, and do not stop tramadol on your own.
Evidence: Supported by human study data.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Tramadol with paracetamol?
5-HTP is turned into serotonin in the body, and tramadol with paracetamol (Tramacet) contains tramadol, which raises serotonin as part of how it works, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with tramadol with paracetamol; if you already take both, tell the prescriber who manages it, and do not stop it on your own.
Evidence: Supported by human study data.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Tranylcypromine?
5-HTP raises serotonin levels. Combined with an MAOI like tranylcypromine, this can produce severe serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Trazodone hydrochloride?
5-HTP is turned into serotonin in the body, and trazodone is an antidepressant that acts on serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with trazodone; if you already take both, tell the prescriber who manages your trazodone, and do not stop trazodone on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Trimipramine?
5-HTP is turned into serotonin in the body, and trimipramine is a tricyclic antidepressant with some effect on serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with trimipramine; if you already take both, tell the prescriber who manages your trimipramine, and do not stop trimipramine on your own.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Venlafaxine?
5-HTP raises serotonin levels. Combined with an SNRI like venlafaxine, it can cause serotonin syndrome. Do not combine.
Evidence: Supported by human study data.
Red Does 5-HTP interact with Vortioxetine?
5-HTP is turned into serotonin in the body, and vortioxetine is an antidepressant that works mainly through serotonin, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with vortioxetine; if you already take both, tell the prescriber who manages your vortioxetine, and do not stop vortioxetine on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Red Does 5-HTP interact with Zolmitriptan?
5-HTP is turned into serotonin in the body, and zolmitriptan is a migraine medicine that acts on serotonin receptors, so taking the two together can cause serotonin syndrome (agitation, sweating, tremor, a racing heart, confusion). Do not take 5-HTP with zolmitriptan; if you already take both, tell the prescriber who manages your zolmitriptan, and do not stop zolmitriptan on your own.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
What this list does not say. Pairs not flagged here are not implicitly safe. They are either not yet in our database, or fall outside our inclusion scope. Use the checker below to surface any medication, and submit a missing item if you take something we have not catalogued.
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