instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).Serious - Use Alternative (1)lithium and paliperidone both increase QTc interval. Avoid or Use Alternate Drug.pancuroniumMinor (1)lithium increases effects of pancuronium by unknown mechanism. Minor/Significance Unknown.panobinostatSerious - Use Alternative (1)lithium and panobinostat both increase QTc interval. Avoid or Use Alternate Drug.parecoxibMonitor Closely (1)parecoxib increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.paroxetineMonitor Closely (2)paroxetine and lithium both increase serotonin levels. Modify Therapy/Monitor Closely. lithium and paroxetine both increase QTc interval. Use Caution/Monitor.Minor (1)paroxetine, lithium. Mechanism: unknown. Minor/Significance Unknown. Risk of neurotoxicity.pasireotideMonitor Closely (1)lithium and pasireotide both increase QTc interval. Use Caution/Monitor.pazopanibSerious - Use Alternative (1)lithium and pazopanib both increase QTc interval. Avoid or Use Alternate Drug.pentamidineSerious - Use Alternative (1)lithium and pentamidine both increase QTc interval. Avoid or Use Alternate Drug.pentazocineMonitor Closely (1)lithium and pentazocine both increase serotonin levels. Use Caution/Monitor.perindoprilMonitor Closely (1)perindopril increases toxicity of lithium by unknown mechanism. Use Caution/Monitor. ACE inhibitor induced Na+ depletion may increase reabsorption of lithium from renal tubule.perphenazineMonitor Closely (3)lithium, perphenazine. Other (see comment). Use Caution/Monitor. Comment: Risk of neurotoxicity. Multiple mechanisms involved. lithium, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). lithium and perphenazine both increase QTc interval. Use Caution/Monitor.phenelzineMonitor Closely (1)lithium, phenelzine. Mechanism: unknown. Use Caution/Monitor. Risk of malignant hyperpyrexia. Interactions esp. expected w/non selective MAOIs.Serious - Use Alternative (1)phenelzine and lithium both increase serotonin levels. Avoid or Use Alternate Drug.phenytoinMinor (1)phenytoin increases toxicity of lithium by unknown mechanism. Minor/Significance Unknown.pimavanserinMonitor Closely (1)lithium, pimavanserin. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).Serious - Use Alternative (1)lithium and pimavanserin both increase QTc interval. Avoid or Use Alternate Drug.pimozideMonitor Closely (1)lithium, pimozide. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).Serious - Use Alternative (1)lithium and pimozide both increase QTc interval. Contraindicated.piroxicamMonitor Closely (1)piroxicam increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.pitolisantSerious - Use Alternative (1)lithium and pitolisant both increase QTc interval. Avoid or Use Alternate Drug.ponesimodSerious - Use Alternative (1)lithium and ponesimod both increase QTc interval. Avoid or Use Alternate Drug.posaconazoleMonitor Closely (1)lithium and posaconazole both increase QTc interval. Use Caution/Monitor.potassium iodideMonitor Closely (1)potassium iodide, lithium. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Concomitant use with antithyroid drugs may potentiate the hypothyroid and goitrogenic effects of potassium iodide.primaquineMonitor Closely (1)lithium and primaquine both increase QTc interval. Use Caution/Monitor.procainamideSerious - Use Alternative (1)lithium and procainamide both increase QTc interval. Avoid or Use Alternate Drug.procarbazineMonitor Closely (1)lithium, procarbazine. Mechanism: unknown. Use Caution/Monitor.Serious - Use Alternative (1)procarbazine and lithium both increase serotonin levels. Avoid or Use Alternate Drug.prochlorperazineMonitor Closely (2)lithium, prochlorperazine. Other (see comment). Use Caution/Monitor. Comment: Risk of neurotoxicity. Multiple mechanisms involved. lithium and prochlorperazine both decrease QTc interval. Use Caution/Monitor.promazineMonitor Closely (1)lithium, promazine. Other (see comment). Use Caution/Monitor. Comment: Risk of neurotoxicity. Multiple mechanisms involved.promethazineMonitor Closely (2)lithium, promethazine. Other (see comment). Use Caution/Monitor. Comment: Risk of neurotoxicity. Multiple mechanisms involved. lithium and promethazine both decrease QTc interval. Use Caution/Monitor.propafenoneSerious - Use Alternative (1)lithium and propafenone both increase QTc interval. Avoid or Use Alternate Drug.protriptylineMonitor Closely (2)lithium and protriptyline both increase QTc interval. Use Caution/Monitor. protriptyline and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.Minor (1)lithium, protriptyline. Other (see comment). Minor/Significance Unknown. Comment: Risk of neurotoxicity in geriatric pts. Multiple mechanisms involved.quetiapineMonitor Closely (1)lithium, quetiapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).Serious - Use Alternative (1)lithium and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.quinaprilMonitor Closely (1)quinapril increases toxicity of lithium by unknown mechanism. Use Caution/Monitor. ACE inhibitor induced Na+ depletion may increase reabsorption of lithium from renal tubule.quinidineSerious - Use Alternative (1)lithium and quinidine both increase QTc interval. Avoid or Use Alternate Drug.quinineSerious - Use Alternative (1)lithium and quinine both increase QTc interval. Avoid or Use Alternate Drug.ramiprilMonitor Closely (1)ramipril increases toxicity of lithium by unknown mechanism. Use Caution/Monitor. ACE inhibitor induced Na+ depletion may increase reabsorption of lithium from renal tubule.ranolazineMonitor Closely (1)lithium and ranolazine both increase QTc interval. Use Caution/Monitor.rapacuroniumMinor (1)lithium increases effects of rapacuronium by unknown mechanism. Minor/Significance Unknown.ribociclibSerious - Use Alternative (1)lithium and ribociclib both increase QTc interval. Avoid or Use Alternate Drug.rilpivirineMonitor Closely (1)lithium and rilpivirine both increase QTc interval. Use Caution/Monitor.risperidoneMonitor Closely (2)lithium, risperidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). lithium and risperidone both increase QTc interval. Use Caution/Monitor.rizatriptanMonitor Closely (1)rizatriptan and lithium both increase serotonin levels. Use Caution/Monitor.rocuroniumMinor (1)lithium increases effects of rocuronium by unknown mechanism. Minor/Significance Unknown.romidepsinMonitor Closely (1)lithium and romidepsin both increase QTc interval. Use Caution/Monitor.ropeginterferon alfa 2bSerious - Use Alternative (1)ropeginterferon alfa 2b and lithium both increase Other (see comment). Avoid or Use Alternate Drug. Narcotics, hypnotics or sedatives can produce additive neuropsychiatric side effects. Avoid use and monitor patients receiving the combination for effects of excessive CNS toxicity.sacubitril/valsartanSerious - Use Alternative (2)sacubitril/valsartan increases toxicity of lithium by decreasing renal clearance. Avoid or Use Alternate Drug. sacubitril/valsartan increases levels of lithium by unknown mechanism. Avoid or Use Alternate Drug.salicylates (non-asa)Monitor Closely (1)salicylates (non-asa) increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.salsalateMonitor Closely (1)salsalate increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.SAMeMonitor Closely (1)lithium and SAMe both increase serotonin levels. Use Caution/Monitor.saquinavirSerious - Use Alternative (1)lithium and saquinavir both increase QTc interval. Avoid or Use Alternate Drug.sargramostimMinor (1)lithium increases effects of sargramostim by pharmacodynamic synergism. Minor/Significance Unknown.selegilineMonitor Closely (1)selegiline and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.selegiline transdermalMonitor Closely (1)selegiline transdermal and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.selpercatinibSerious - Use Alternative (1)lithium and selpercatinib both increase QTc interval. Avoid or Use Alternate Drug.sertralineMonitor Closely (2)lithium and sertraline both increase QTc interval. Use Caution/Monitor. sertraline and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.Minor (1)sertraline, lithium. Mechanism: unknown. Minor/Significance Unknown. Risk of neurotoxicity.sevofluraneSerious - Use Alternative (1)sevoflurane and lithium both increase QTc interval. Avoid or Use Alternate Drug.siponimodSerious - Use Alternative (1)lithium and siponimod both increase QTc interval. Avoid or Use Alternate Drug.sodium chlorideMinor (1)sodium chloride, lithium. Other (see comment). Minor/Significance Unknown. Comment: High sodium intake decreases lithium concentration; low sodium may increase lithium levels. Mechanism: Lithium excretion is proportional to salt intake.sodium phosphate rectalSerious - Use Alternative (1)sodium phosphate rectal decreases levels of lithium by Other (see comment). Avoid or Use Alternate Drug. Comment: Sodium phosphates may cause hypernatremia which increases lithium renal clearance; more common with large doses of oral sodium phosphate.sodium polystyrene sulfonateMinor (1)sodium polystyrene sulfonate decreases levels of lithium by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.solifenacinMonitor Closely (1)lithium and solifenacin both increase QTc interval. Use Caution/Monitor.sorafenibSerious - Use Alternative (1)lithium and sorafenib both increase QTc interval. Avoid or Use Alternate Drug.sotagliflozinMonitor Closely (1)sotagliflozin will decrease the level or effect of lithium by Other (see comment). Modify Therapy/Monitor Closely. Concomitant use of an SGLT2 inhibitor with lithium may decrease serum lithium concentrations; monitor serum lithium concentration more frequently during therapy initiation and dosage changessotalolSerious - Use Alternative (1)lithium and sotalol both increase QTc interval. Avoid or Use Alternate Drug.St John's WortMonitor Closely (1)lithium and St John's Wort both increase serotonin levels. Modify Therapy/Monitor Closely.succinylcholineMinor (1)lithium increases effects of succinylcholine by unknown mechanism. Minor/Significance Unknown.sulfasalazineMonitor Closely (1)sulfasalazine increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.sulindacMonitor Closely (1)sulindac increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.sumatriptanMonitor Closely (1)sumatriptan and lithium both increase serotonin levels. Use Caution/Monitor.sumatriptan intranasalMonitor Closely (1)sumatriptan intranasal and lithium both increase serotonin levels. Use Caution/Monitor.sunitinibMonitor Closely (1)lithium and sunitinib both increase QTc interval. Use Caution/Monitor.tacrolimusMonitor Closely (1)lithium and tacrolimus both increase QTc interval. Use Caution/Monitor.teduglutideMonitor Closely (1)teduglutide increases levels of lithium by Other (see comment). Use Caution/Monitor. Comment: Teduglutide may increase absorption of concomitant PO medications; caution with with drugs requiring titration or those with a narrow therapeutic index; dose adjustment may be necessary.telavancinMonitor Closely (1)lithium and telavancin both increase QTc interval. Use Caution/Monitor.telmisartanSerious - Use Alternative (1)telmisartan increases toxicity of lithium by decreasing renal clearance. Avoid or Use Alternate Drug.tetrabenazineSerious - Use Alternative (1)lithium and tetrabenazine both increase QTc interval. Avoid or Use Alternate Drug.theophyllineMinor (1)theophylline decreases levels of lithium by increasing renal clearance. Minor/Significance Unknown.thioridazineContraindicated (1)lithium and thioridazine both increase QTc interval. Contraindicated.Monitor Closely (1)lithium, thioridazine. Other (see comment). Use Caution/Monitor. Comment: Risk of neurotoxicity. Multiple mechanisms involved.thiothixeneMonitor Closely (2)lithium, thiothixene. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). lithium and thiothixene both increase QTc interval. Use Caution/Monitor.tinidazoleMonitor Closely (1)tinidazole increases effects of lithium by unknown mechanism. Use Caution/Monitor. Metronidazole has been reported to elevate serum lithium levels. Tinidazole effects on lithium are unknown. Consider monitoring serum lithium and creatinine levels after several days of concomitant use with lithium and tinidazole to detect potential lithium intoxication.tolfenamic acidMonitor Closely (1)tolfenamic acid increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.tolmetinMonitor Closely (1)tolmetin increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.topiramateMonitor Closely (1)topiramate increases levels of lithium by unspecified interaction mechanism. Use Caution/Monitor. Increase in lithium exposure may occur with doses of up to 600 mg/day; monitor lithium levels when coadministered with high-dose topiramate .toremifeneSerious - Use Alternative (1)lithium and toremifene both increase QTc interval. Avoid or Use Alternate Drug.tramadolMonitor Closely (1)lithium and tramadol both increase serotonin levels. Use Caution/Monitor.trandolaprilMonitor Closely (1)trandolapril increases toxicity of lithium by unknown mechanism. Use Caution/Monitor. ACE inhibitor induced Na+ depletion may increase reabsorption of lithium from renal tubule.tranylcypromineMonitor Closely (1)lithium, tranylcypromine. Mechanism: unknown. Use Caution/Monitor. Risk of malignant hyperpyrexia. Interactions esp. expected w/non selective MAOIs.Serious - Use Alternative (1)tranylcypromine and lithium both increase serotonin levels. Avoid or Use Alternate Drug.trazodoneMonitor Closely (1)trazodone and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)lithium and trazodone both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)lithium, trazodone. Other (see comment). Minor/Significance Unknown. Comment: Risk of neurotoxicity in geriatric pts. Multiple mechanisms involved. trazodone, lithium. Mechanism: unknown. Minor/Significance Unknown. Risk of neurotoxicity.triclabendazoleMonitor Closely (1)lithium and triclabendazole both increase QTc interval. Use Caution/Monitor.trifluoperazineMonitor Closely (3)lithium, trifluoperazine. Other (see comment). Use Caution/Monitor. Comment: Risk of neurotoxicity. Multiple mechanisms involved. lithium, trifluoperazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). lithium and trifluoperazine both decrease QTc interval. Use Caution/Monitor.trimipramineMonitor Closely (2)trimipramine and lithium both increase serotonin levels. Modify Therapy/Monitor Closely. lithium and trimipramine both increase QTc interval. Use Caution/Monitor.Minor (1)lithium, trimipramine. Other (see comment). Minor/Significance Unknown. Comment: Risk of neurotoxicity in geriatric pts. Multiple mechanisms involved.triptorelinMonitor Closely (1)lithium and triptorelin both increase QTc interval. Use