Editing Chlorpromazine (section)

==Interactions==
{{cleanup section|reason=Too much use of "also"; unclear structure/organization, especially due to heavy reliance on one source.|date=January 2022}}

Consuming food prior to taking chlorpromazine orally limits its absorption; likewise, cotreatment with [[benztropine]] can also reduce chlorpromazine absorption.<ref name = TGA/> [[alcohol (drug)|Alcohol]] can also reduce chlorpromazine absorption.<ref name = TGA/> Antacids slow chlorpromazine absorption.<ref name = TGA/> [[Lithium (medication)|Lithium]] and chronic treatment with [[barbiturates]] can increase chlorpromazine clearance significantly.<ref name = TGA/> [[Tricyclic antidepressants]] (TCAs) can decrease chlorpromazine clearance and hence increase chlorpromazine exposure.<ref name = TGA/> Cotreatment with [[CYP1A2]] inhibitors like [[ciprofloxacin]], [[fluvoxamine]] or [[vemurafenib]] can reduce chlorpromazine clearance and hence increase exposure and potentially also adverse effects.<ref name = TGA/> Chlorpromazine can also potentiate the CNS depressant effects of drugs like [[barbiturates]], [[benzodiazepines]], [[opioids]], lithium and anesthetics and hence increase the potential for adverse effects such as [[respiratory depression]] and [[sedation]].<ref name =TGA/>

Chlorprozamine is also a moderate inhibitor of [[CYP2D6]] and a substrate for [[CYP2D6]] and hence can inhibit its own metabolism.<ref name =GG/> It can also inhibit the clearance of [[CYP2D6]] substrates such as [[dextromethorphan]], potentiating their effects.<ref name = GG/> Other drugs like [[codeine]] and [[tamoxifen]], which require [[CYP2D6]]-mediated activation into their respective active metabolites, may have their therapeutic effects attenuated.<ref name = GG/> Likewise, [[CYP2D6]] inhibitors such as [[paroxetine]] or [[fluoxetine]] can reduce chlorpromazine clearance, increasing serum levels of chlorpromazine and potentially its adverse effects.<ref name = TGA/> Chlorpromazine also reduces [[phenytoin]] levels and increases [[valproic acid]] levels.<ref name =TGA/> It also reduces [[propranolol]] clearance and antagonizes the therapeutic effects of [[antidiabetic]] agents, [[levodopa]] (a [[Parkinson's]] medication. This is likely because chlorpromazine antagonizes the D<sub>2</sub> receptor which is one of the receptors dopamine, a levodopa metabolite, activates), [[amphetamine]]s and [[anticoagulant]]s.<ref name = TGA/> It may also interact with anticholinergic drugs such as [[orphenadrine]] to produce [[hypoglycaemia]] (low blood sugar).<ref name = TGA/>

Chlorpromazine may also interact with [[epinephrine]] (adrenaline) to produce a paradoxical fall in blood pressure.<ref name = TGA/> [[Monoamine oxidase inhibitors]] (MAOIs) and [[thiazide]] diuretics may also accentuate the orthostatic hypotension experienced by those receiving chlorpromazine treatment.<ref name = TGA/> Quinidine may interact with chlorpromazine to increase [[myocardium|myocardial]] depression.<ref name = TGA/> Likewise, it may also antagonize the effects of [[clonidine]] and [[guanethidine]].<ref name = TGA/> It also may reduce the seizure threshold and hence a corresponding titration of anticonvulsant treatments should be considered.<ref name = TGA/> [[Prochlorperazine]] and [[desferrioxamine]] may also interact with chlorpromazine to produce transient metabolic [[encephalopathy]].<ref name = TGA/>

Other drugs that prolong the QT interval, such as [[quinidine]], [[verapamil]], [[amiodarone]], [[sotalol]] and [[methadone]], may also interact with chlorpromazine to produce additive [[QT interval]] prolongation.<ref name = TGA/>

Chlorpromazine is a [[serotonin]] [[5-HT2A receptor|5-HT<sub>2A</sub> receptor]] [[receptor antagonist|antagonist]] and has been found to reduce the [[hallucinogen]]ic effects of [[serotonergic psychedelic]]s like [[LSD]].<ref name="Thomas2024">{{cite book | last=Thomas | first=Kelan | title=Toxicology and Pharmacological Interactions of Classic Psychedelics | publisher=Springer Berlin Heidelberg | publication-place=Berlin, Heidelberg | date=2024 | doi=10.1007/7854_2024_508 | url=https://link.springer.com/10.1007/7854_2024_508 | access-date=14 May 2025 | quote=Chlorpromazine, an antipsychotic with relatively strong binding affinity for 5-HT2A (Ki = 2 nM), pretreatment dosed at 25–100 mg dosed 30 min prior to LSD 15–60 μg also reduced the intensity of psychedelic subjective effects (Isbell 1957; Murphree 1962; Maheux et al. 2005).}}</ref>