signs of respiratory depression and sedation. Increased risk of hypotension if ability to maintain blood pressure has been compromised by a reduced blood volume or concurrent administration of certain CNS depressant drugs (eg, phenothiazines or general anesthetics).olodaterol inhaledMonitor Closely (1)fluphenazine and olodaterol inhaled both increase QTc interval. Use Caution/Monitor. Drugs that prolong the QTc interval and may potentiate the effects of beta2 agonists on the cardiovascular system; increased risk of ventricular arrhythmiasolopatadine intranasalSerious - Use Alternative (1)fluphenazine and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment. onabotulinumtoxinAMonitor Closely (3)onabotulinumtoxinA decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. onabotulinumtoxinA decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of onabotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.ondansetronSerious - Use Alternative (1)fluphenazine and ondansetron both increase QTc interval. Avoid or Use Alternate Drug. Avoid with congenital long QT syndrome; ECG monitoring recommended with concomitant medications that prolong QT interval, electrolyte abnormalities, CHF, or bradyarrhythmias.opium tinctureMonitor Closely (1)opium tincture and fluphenazine both increase sedation. Use Caution/Monitor.orphenadrineMonitor Closely (1)orphenadrine and fluphenazine both increase sedation. Use Caution/Monitor.osilodrostatMonitor Closely (1)osilodrostat and fluphenazine both increase QTc interval. Use Caution/Monitor.osimertinibMonitor Closely (1)osimertinib and fluphenazine both increase QTc interval. Use Caution/Monitor. Conduct periodic monitoring with ECGs and electrolytes in patients taking drugs known to prolong the QTc interval.oxaliplatinMonitor Closely (1)oxaliplatin and fluphenazine both increase QTc interval. Use Caution/Monitor.oxazepamMonitor Closely (1)oxazepam and fluphenazine both increase sedation. Use Caution/Monitor.oxybutyninMonitor Closely (3)oxybutynin decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. oxybutynin decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of oxybutynin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.Minor (1)oxybutynin increases toxicity of fluphenazine by unspecified interaction mechanism. Minor/Significance Unknown.oxybutynin topicalMonitor Closely (3)oxybutynin topical decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. oxybutynin topical decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of oxybutynin topical by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.Minor (1)oxybutynin topical increases toxicity of fluphenazine by unspecified interaction mechanism. Minor/Significance Unknown.oxybutynin transdermalMonitor Closely (3)oxybutynin transdermal decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. oxybutynin transdermal decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of oxybutynin transdermal by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.Minor (1)oxybutynin transdermal increases toxicity of fluphenazine by unspecified interaction mechanism. Minor/Significance Unknown.oxycodoneMonitor Closely (1)oxycodone and fluphenazine both increase sedation. Use Caution/Monitor.oxymorphoneMonitor Closely (1)oxymorphone and fluphenazine both increase sedation. Use Caution/Monitor.ozanimodMonitor Closely (1)ozanimod and fluphenazine both increase QTc interval. Modify Therapy/Monitor Closely. The potential additive effects on heart rate, treatment with ozanimod should generally not be initiated in patients who are concurrently treated with QT prolonging drugs with known arrhythmogenic properties.paliperidoneMonitor Closely (3)fluphenazine and paliperidone both increase QTc interval. Modify Therapy/Monitor Closely. fluphenazine and paliperidone both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. fluphenazine and paliperidone both increase sedation. Use Caution/Monitor.pancuroniumMonitor Closely (3)pancuronium decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. pancuronium decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of pancuronium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.papaveretumMonitor Closely (1)papaveretum and fluphenazine both increase sedation. Use Caution/Monitor.papaverineMonitor Closely (1)fluphenazine and papaverine both increase sedation. Use Caution/Monitor.parecoxibMinor (1)parecoxib will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.paroxetineMonitor Closely (1)paroxetine, fluphenazine. 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 (2)fluphenazine and paroxetine both increase QTc interval. Avoid or Use Alternate Drug. paroxetine will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.pasireotideMonitor Closely (1)fluphenazine and pasireotide both increase QTc interval. Modify Therapy/Monitor Closely.pazopanibMonitor Closely (1)fluphenazine and pazopanib both increase QTc interval. Use Caution/Monitor.pentamidineContraindicated (1)fluphenazine and pentamidine both increase QTc interval. Contraindicated.pentazocineMonitor Closely (1)pentazocine and fluphenazine both increase sedation. Use Caution/Monitor.pentobarbitalMonitor Closely (1)pentobarbital and fluphenazine both increase sedation. Use Caution/Monitor.perindoprilMinor (1)fluphenazine increases effects of perindopril by unspecified interaction mechanism. Minor/Significance Unknown.perphenazineMonitor Closely (2)fluphenazine and perphenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. fluphenazine and perphenazine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)fluphenazine and perphenazine both increase QTc interval. Avoid or Use Alternate Drug.Minor (1)perphenazine will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.phendimetrazineMonitor Closely (2)fluphenazine, phendimetrazine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only. fluphenazine increases and phendimetrazine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.phenelzineMonitor Closely (1)phenelzine, fluphenazine. 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).phenobarbitalMonitor Closely (1)phenobarbital and fluphenazine both increase sedation. Use Caution/Monitor.phentermineMonitor Closely (2)fluphenazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only. fluphenazine increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.phenylephrineMonitor Closely (2)fluphenazine, phenylephrine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only. fluphenazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.phenylephrine POMonitor Closely (2)fluphenazine, phenylephrine PO. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only. fluphenazine increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .pholcodineMonitor Closely (1)fluphenazine and pholcodine both increase sedation. Use Caution/Monitor.pimozideContraindicated (1)fluphenazine and pimozide both increase QTc interval. Contraindicated.Monitor Closely (2)fluphenazine and pimozide both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. fluphenazine and pimozide both increase sedation. Use Caution/Monitor.pirbuterolMonitor Closely (1)fluphenazine increases and pirbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.porfimerMonitor Closely (1)fluphenazine, porfimer. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Enhanced photosensitivity.posaconazoleMonitor Closely (1)fluphenazine and posaconazole both increase QTc interval. Modify Therapy/Monitor Closely.pralidoximeMonitor Closely (3)pralidoxime decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. pralidoxime decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of pralidoxime by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.pramipexoleSerious - Use Alternative (1)fluphenazine decreases effects of pramipexole by pharmacodynamic antagonism. Contraindicated.primaquineMonitor Closely (1)primaquine and fluphenazine both increase QTc interval. Use Caution/Monitor.primidoneMonitor Closely (1)primidone and fluphenazine both increase sedation. Use Caution/Monitor.procainamideContraindicated (1)fluphenazine and procainamide both increase QTc interval. Contraindicated.procarbazineMonitor Closely (2)procarbazine, fluphenazine. 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). procarbazine, fluphenazine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Excessive sedation.prochlorperazineMonitor Closely (2)fluphenazine and prochlorperazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. fluphenazine and prochlorperazine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)fluphenazine and prochlorperazine both increase QTc interval. Avoid or Use Alternate Drug.promazineSerious - Use Alternative (1)fluphenazine and promazine both increase QTc interval. Avoid or Use Alternate Drug.promethazineMonitor Closely (3)promethazine, fluphenazine. 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). fluphenazine and promethazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. promethazine and fluphenazine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)fluphenazine and promethazine both increase QTc interval. Avoid or Use Alternate Drug.propafenoneMonitor Closely (1)propafenone will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.propanthelineMonitor Closely (3)propantheline decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. propantheline decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of propantheline by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.propofolMonitor Closely (1)propofol and fluphenazine both increase sedation. Use Caution/Monitor.propylhexedrineMonitor Closely (2)fluphenazine, propylhexedrine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only. fluphenazine increases and propylhexedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.protriptylineMonitor Closely (1)fluphenazine and protriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)fluphenazine and protriptyline both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)protriptyline, fluphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. protriptyline, fluphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.pseudoephedrineMonitor Closely (1)fluphenazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Consider avoiding use of pseudoephedrine in patients receiving phenothiazines (especially thioridazine) due to the potential risk of cardiac arrhythmia or sudden death. Monitor for evidence of ventricular arrhythmias during concomitant use.pyrimethamineMinor (1)pyrimethamine increases levels of fluphenazine by decreasing metabolism. Minor/Significance Unknown.quazepamMonitor Closely (1)quazepam and fluphenazine both increase sedation. Use Caution/Monitor.quetiapineMonitor Closely (2)fluphenazine and quetiapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. fluphenazine and quetiapine both increase sedation. Use Caution/Monitor.quinacrineMinor (1)quinacrine will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.quinaprilMinor (1)fluphenazine increases effects of quinapril by unspecified interaction mechanism. Minor/Significance Unknown.quinidineContraindicated (1)fluphenazine and quinidine both increase QTc interval. Contraindicated.Monitor Closely (1)quinidine will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)quinidine, fluphenazine. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Additive cardiac effects.quinineMonitor Closely (1)fluphenazine and quinine both increase QTc interval. Use Caution/Monitor.ramelteonMonitor Closely (1)fluphenazine and ramelteon both increase sedation. Use Caution/Monitor.ramiprilMinor (1)fluphenazine increases effects of ramipril by unspecified interaction mechanism. Minor/Significance Unknown.ranolazineMonitor Closely (1)fluphenazine and ranolazine both increase QTc interval. Modify Therapy/Monitor Closely.Minor (1)ranolazine will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.rapacuroniumMonitor Closely (3)rapacuronium decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. rapacuronium decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of rapacuronium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.remimazolamMonitor Closely (1)remimazolam, fluphenazine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.ribociclibMonitor Closely (1)ribociclib increases toxicity of fluphenazine by QTc interval. Use Caution/Monitor.rimabotulinumtoxinBMonitor Closely (1)fluphenazine increases effects of rimabotulinumtoxinB by pharmacodynamic synergism. Use Caution/Monitor. Anticholinergics may enhance botulinum toxin effects. Closely monitor for increased neuromuscular blockade.risperidoneMonitor Closely (3)fluphenazine and risperidone both increase QTc interval. Modify Therapy/Monitor Closely. fluphenazine and risperidone both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. fluphenazine and risperidone both increase sedation. Use Caution/Monitor.ritonavirMinor (1)ritonavir will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.rizatriptanMonitor Closely (1)rizatriptan, fluphenazine. unspecified interaction mechanism. Use Caution/Monitor.