Phenothiazines

Epinephrine should not be used to counteract circulatory collapse or hypotension caused by phenothiazines; may result in further lowering of blood pressure.

Increased risk of Torsade de Pointes. Avoid concomitant use.

Cabergoline should not be administered concurrently with phenothiazines, which are D2-antagonists that may antagonize cabergoline's dopaminergic effects.

Contraindicated due to potential risk of torsade de pointes-type ventricular tachycardia when prolonging QT interval.

Do not use epinephrine to counteract circulatory collapse from phenothiazines; reversal of pressor effects may cause further blood pressure lowering.

Should not be administered concomitantly due to possibility of augmented phototoxicity as phenothiazines are known photosensitizers.

Severe hypothermia possible with acetaminophen; additive CNS depressant effects with dihydrocodeine.

Phototoxic agents that may cause severe phototoxic skin reaction (severe sunburn). Avoid for 24 hours before and after ALA administration.

Inhibit P450 2D6, may increase amitriptyline levels and toxicity in normal metabolizers.

Dopamine receptor antagonists may diminish the effectiveness of bromocriptine, and bromocriptine may diminish their effectiveness. Concurrent use not recommended.

Concurrent use with local anesthetic solutions containing epinephrine or norepinephrine may produce severe, prolonged hypotension or hypertension.

Potentiate CNS-depressant action of clonazepam.

Actions of benzodiazepines may be potentiated by phenothiazines.

May potentiate the action of diazepam. Careful consideration of pharmacology needed when combined.

Should be avoided due to risk of QT prolongation and torsades de pointes.

May decrease blood glucose lowering effect of LANTUS. Dosage increases and increased glucose monitoring may be required.

May produce severe prolonged hypotension or hypertension. Concurrent use should generally be avoided; careful monitoring essential if necessary.

Additive depression of the central nervous system when administered with lorazepam injection.

Substrates for P450 2D6 that inhibit the enzyme, potentially increasing nortriptyline plasma concentrations to toxic levels.

Additive CNS depression with potential respiratory depression, hypotension, profound sedation, or coma. Dose reduction recommended.

May produce severe, prolonged hypotension or hypertension; concurrent use should generally be avoided.

Dopamine antagonists may diminish the effectiveness of ropinirole. Use in patients with major psychotic disorders only if potential benefits outweigh risks.

Phenothiazines produce hyperglycemia and may lead to loss of blood glucose control in patients receiving Acarbose. Close observation for loss of glucose control is recommended.

May produce hyperglycemia and lead to loss of glycemic control.

Phenothiazines inhibit cytochrome P450 2D6 activity, which may increase amoxapine plasma concentrations and require dose adjustment.

May reduce or reverse the pressor effect of epinephrine; concurrent use should be avoided but careful monitoring is essential if necessary.

May reduce or reverse the pressor effect of epinephrine; concurrent use should generally be avoided but if necessary requires careful patient monitoring.

Antipsychotic drugs such as phenothiazines may interact with benztropine mesylate; concurrent use requires monitoring per WARNINGS section.

May reduce or reverse the pressor effect of epinephrine in local anesthetic solutions.

May reduce or reverse the pressor effect of epinephrine. Concurrent use should generally be avoided; if necessary, careful patient monitoring is essential.

Dopamine D2 receptor antagonists may reduce the therapeutic effects of levodopa; patients should be carefully observed for loss of therapeutic response.

Dopamine D2 receptor antagonists may reduce the therapeutic effects of levodopa; patients should be carefully observed for loss of response.

Dopamine D2 receptor antagonists may reduce therapeutic effects of levodopa; patients should be carefully observed for loss of therapeutic response.

Dopamine D2 receptor antagonists may reduce therapeutic effects of levodopa.

Substrates for P450 2D6 that inhibit the enzyme and may increase clomipramine plasma concentrations.

Produce hyperglycemia and may lead to loss of glycemic control when used with XIGDUO XR.

Inhibit P450 2D6 and are substrates for the enzyme; may increase desipramine concentrations; dose adjustment and monitoring recommended.

Phenothiazines may reduce or reverse the pressor effect of epinephrine; concurrent use should generally be avoided and requires careful patient monitoring.

Antipsychotic agents may increase certain actions or side effects of dicyclomine hydrochloride.

Concurrent use may antagonize the anorectic effect of diethylpropion.

Suppress dopaminergic renal and mesenteric vasodilation induced by low-dose dopamine.

May produce hyperglycemia and lead to loss of glycemic control; monitor closely.

May produce hyperglycemia and lead to loss of glycemic control; close monitoring recommended.

May potentiate the action of estazolam; careful consideration of CNS effects needed.

Dopamine D2 receptor antagonist may reduce effectiveness of foslevodopa. Monitor for worsening Parkinson's symptoms.

May increase phenytoin serum levels; monitoring of phenytoin levels recommended.

Phenothiazines may produce hyperglycemia and lead to loss of control of glyburide. Patients should be closely observed for loss of control.

May reduce glucose-lowering effect of glimepiride, leading to worsening glycemic control.

Phenothiazines may produce hyperglycemia and lead to loss of glycemic control. Patient should be observed closely for loss of control when initiated or withdrawn.

Phenothiazines may produce hyperglycemia and lead to loss of blood glucose control. Patient should be closely observed for loss of blood glucose control.

Phenothiazines tend to produce hyperglycemia and may lead to loss of blood glucose control. Close observation required.

Concurrent use may intensify antimuscarinic effects and increase anticholinergic side effects.

Additive CNS depressant effects; reduced dosage of hydromorphone recommended to avoid excessive effects.

Additive adverse effects from cholinergic blockade may occur when combined with hyoscyamine sulfate.

May decrease blood glucose lowering effect. Dose adjustment and increased glucose monitoring may be required.

May decrease blood glucose lowering effect. Dose adjustment and increased glucose monitoring may be required.

May decrease blood glucose lowering effect. Dosage increases and increased glucose monitoring may be required.

May decrease blood glucose-lowering effect; dosage increases and increased glucose monitoring may be required.

May decrease blood glucose lowering effect of insulin detemir. Dosage increases and increased glucose monitoring may be required.

May decrease the blood glucose lowering effect. Dose increases and increased glucose monitoring may be required.

May decrease blood glucose lowering effect. Dosage increases and increased glucose monitoring may be required.

May decrease blood glucose lowering effect. Dosage increases and increased glucose monitoring may be required.

May decrease blood glucose lowering effect; dose adjustment and increased glucose monitoring may be required.

May decrease the blood glucose lowering effect. Dose adjustment and increased frequency of glucose monitoring may be required.

May decrease blood glucose lowering effect. Dose increases and increased glucose monitoring may be required.

Phenothiazines (dopamine D2 receptor antagonists) may reduce the effectiveness of levodopa. Monitor patients for worsening Parkinson's symptoms.

May reduce or reverse the pressor effect of epinephrine in lidocaine solutions; concurrent use should generally be avoided.

Phenothiazines may produce hyperglycemia and lead to loss of glycemic control. Close monitoring of glycemic control is recommended.

Phenothiazines may reduce or reverse the pressor effect of epinephrine. Concurrent use should generally be avoided.

May reduce or reverse the pressor effect of epinephrine in mepivacaine solutions.

Produce hyperglycemia and may lead to loss of glycemic control when used with metformin.

May produce hyperglycemia and lead to loss of glycemic control. Monitor patient closely for loss of blood glucose control.

Drugs that produce hyperglycemia and may lead to loss of glycemic control; monitor blood glucose.

May produce hyperglycemia and lead to loss of glycemic control during metformin therapy; monitor blood glucose.

May produce hyperglycemia and lead to loss of glycemic control when used with metformin.

Phenothiazines are reported to antagonize the CNS stimulant action of methamphetamine.

Extrapyramidal effects of phenothiazines can be potentiated by metyrosine's inhibition of catecholamine synthesis. Caution should be observed.

Concurrent use with glycopyrrolate may intensify antimuscarinic effects and increase anticholinergic side effects.

May increase phenytoin serum levels; monitoring of phenytoin levels recommended.

May increase phenytoin serum levels; monitoring of phenytoin levels recommended.

Concomitant use may increase the risk of photosensitivity reaction. Avoid concomitant use with other photosensitizing agents.

Dopamine antagonists may diminish the effectiveness of pramipexole.

Dopamine antagonists may diminish the effectiveness of pramipexole dihydrochloride.

Neuroleptic dopamine antagonists that may reduce the efficacy of ropinirole tablets.

May produce hyperglycemia and lead to loss of glycemic control. Monitor blood glucose closely during concomitant use.

Phenothiazines may reduce or reverse the pressor effect of epinephrine. Concurrent use should generally be avoided; careful patient monitoring is essential if necessary.

May reduce or reverse the pressor effect of epinephrine in local anesthetic solutions. Concurrent use should generally be avoided.

Other photosensitizing agents that could increase the potential for skin photosensitivity reactions.

Antipsychotic drug phenothiazines interact with benztropine; interaction details referenced in WARNINGS section.