Promethazine and Phenylephrine
Name: Promethazine and Phenylephrine
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What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of high or low blood pressure like very bad headache or dizziness, passing out, change in eyesight.
- Fast or slow heartbeat.
- Trouble passing urine.
- Feeling very tired or weak.
- Hallucinations (seeing or hearing things that are not there).
- Mood changes.
- Ringing in ears.
- Seizures.
- Any unexplained bruising or bleeding.
- Trouble controlling body movements, twitching, change in balance, trouble swallowing or speaking.
- Change in eyesight.
- Yellow skin or eyes.
- A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your doctor right away if you have any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or are sweating a lot.
- This medicine may cause very bad and sometimes deadly breathing problems. Call your doctor right away if you have slow, shallow, or trouble breathing.
- Low white blood cell counts have rarely happened with promethazine and phenylephrine. This may lead to a higher chance of getting an infection. Tell your doctor if you have ever had a low white blood cell count. Call your doctor right away if you have signs of infection like fever, chills, or sore throat.
Adverse Reactions
To report SUSPECTED ADVERSE REACTIONS, contact Hi-Tech Pharmacal Co., Inc. at 1-800-262-9010 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Promethazine
Central Nervous System - Drowsiness is the most prominent CNS effect of this drug. Sedation, somnolence, blurred vision, dizziness; confusion, disorientation, and extrapyramidal symptoms such as oculogyric crisis, torticollis, and tongue protrusion; lassitude, tinnitus, incoordination, fatigue, euphoria, nervousness, diplopia, insomnia, tremors, convulsive seizures, excitation, catatonic-like states, hysteria. Hallucinations have also been reported.
Cardiovascular - Increased or decreased blood pressure, tachycardia, bradycardia, faintness.
Dermatologic - Dermatitis, photosensitivity, urticaria.
Hematologic - Leukopenia, thrombocytopenia, thrombocytopenic purpura, agranulocytosis.
Gastrointestinal - Dry mouth, nausea, vomiting, jaundice.
Respiratory - Asthma, nasal stuffiness, respiratory depression (potentially fatal) and apnea (potentially fatal). (See WARNINGS-Promethazine; Respiratory Depression.)
Other - Angioneurotic edema. Neuroleptic malignant syndrome (potentially fatal) has also been reported. (See WARNINGS-Promethazine; Neuroleptic Malignant Syndrome.)
Paradoxical Reactions - Hyperexcitability and abnormal movements have been reported in patients following a single administration of promethazine HCl. Consideration should be given to the discontinuation of promethazine HCl and to the use of other drugs if these reactions occur. Respiratory depression, nightmares, delirium, and agitated behavior have also been reported in some of these patients.
Phenylephrine
Nervous System – Restlessness, anxiety, nervousness and dizziness.
Cardiovascular – Hypertension (see “WARNINGS”).
Other – Precordial pain, respiratory distress, tremor, and weakness.
Dosage and administration
Promethazine hydrochloride and phenylephrine hydrochloride syrup is contraindicated for children under 2 years of age (see WARNINGS-Black Box Warning and Use in Pediatric Patients).
The recommended doses are given in the following table:
Adults And Children 12 Years And Over
1 teaspoonful (5 mL) every 4 to 6 hours, not to exceed 6 teaspoonsful (30 mL) in 24 hours.
Children 6 To Under 12 Years Of Age
½ to 1 teaspoonful (2.5 to 5 mL) every 4 to 6 hours, not to exceed 6 teaspoonsful (30 mL) in 24 hours.
Children 2 To Under 6 Years Of Age
¼ to ½ teaspoonful (1.25 to 2.5 mL) every 4 to 6 hours.
Brand Names U.S.
- Promethazine VC
Contraindications
Hypersensitivity to promethazine, phenylephrine, or any component of the formulation (cross-reactivity between phenothiazines may occur;) treatment of lower respiratory tract symptoms, including asthma; comatose states; hypertension; peripheral vascular insufficiency; concurrent use with MAO inhibitor therapy; children <2 years of age
Dosing Pediatric
Upper respiratory symptoms: Oral:
Children 2 to <6 years: 1.25 to 2.5 mL (promethazine 1.56 to 3.12 mg/phenylephrine 1.25 to 2.5 mg) every 4 to 6 hours
Children 6 to <12 years: 2.5 to 5 mL (promethazine 3.12 to 6.25 mg/phenylephrine 2.5 to 5 mg) every 4 to 6 hours; maximum: 30 mL (promethazine 37.5 mg/phenylephrine 30 mg)/24 hours
Children ≥12 years and Adolescents: Refer to adult dosing.
Dosing Hepatic Impairment
Adults: There are no dosage adjustments provided in the manufacturer’s labeling; use with caution (cholestatic jaundice has been reported with use).
Children ≥2 years and Adolescents: The manufacturer recommends to avoid use in pediatric patients with signs and symptoms of hepatic disease (extrapyramidal symptoms caused by promethazine may be confused with CNS signs of hepatic disease).
Drug Interactions
Abiraterone Acetate: May increase the serum concentration of CYP2D6 Substrates. Management: Avoid concurrent use of abiraterone with CYP2D6 substrates that have a narrow therapeutic index whenever possible. When concurrent use is not avoidable, monitor patients closely for signs/symptoms of toxicity. Consider therapy modification
AbobotulinumtoxinA: Anticholinergic Agents may enhance the anticholinergic effect of AbobotulinumtoxinA. Monitor therapy
Acetaminophen: May increase the serum concentration of Phenylephrine (Systemic). Monitor therapy
Acetylcholinesterase Inhibitors: Anticholinergic Agents may diminish the therapeutic effect of Acetylcholinesterase Inhibitors. Acetylcholinesterase Inhibitors may diminish the therapeutic effect of Anticholinergic Agents. Monitor therapy
Aclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination
Alcohol (Ethyl): CNS Depressants may enhance the CNS depressant effect of Alcohol (Ethyl). Monitor therapy
Alpha1-Blockers: May diminish the vasoconstricting effect of Alpha1-Agonists. Similarly, Alpha1-Agonists may antagonize Alpha1-Blocker vasodilation. Monitor therapy
Amantadine: May enhance the anticholinergic effect of Anticholinergic Agents. Monitor therapy
Amifampridine: May diminish the anticholinergic effect of Anticholinergic Agents. Anticholinergic Agents may diminish the therapeutic effect of Amifampridine. Monitor therapy
Analgesics (Opioid): CNS Depressants may enhance the CNS depressant effect of Analgesics (Opioid). Management: Avoid concomitant use of opioid analgesics and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification
Anticholinergic Agents: May enhance the adverse/toxic effect of other Anticholinergic Agents. Monitor therapy
Antiemetics (5HT3 Antagonists): May enhance the serotonergic effect of Serotonin Modulators. This could result in serotonin syndrome. Monitor therapy
Antipsychotic Agents: Serotonin Modulators may enhance the adverse/toxic effect of Antipsychotic Agents. Specifically, serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotic Agents may enhance the serotonergic effect of Serotonin Modulators. This could result in serotonin syndrome. Monitor therapy
Asunaprevir: May increase the serum concentration of CYP2D6 Substrates. Consider therapy modification
AtoMOXetine: May enhance the hypertensive effect of Sympathomimetics. AtoMOXetine may enhance the tachycardic effect of Sympathomimetics. Monitor therapy
Azelastine (Nasal): CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). Avoid combination
Benzylpenicilloyl Polylysine: Alpha1-Agonists may diminish the diagnostic effect of Benzylpenicilloyl Polylysine. Management: Consider use of a histamine skin test as a positive control to assess a patient's ability to mount a wheal and flare response. Consider therapy modification
Blonanserin: CNS Depressants may enhance the CNS depressant effect of Blonanserin. Consider therapy modification
Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Buprenorphine: CNS Depressants may enhance the CNS depressant effect of Buprenorphine. Management: Consider reduced doses of other CNS depressants, and avoiding such drugs in patients at high risk of buprenorphine overuse/self-injection. Initiate buprenorphine patches (Butrans brand) at 5 mcg/hr in adults when used with other CNS depressants. Consider therapy modification
Cannabis: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Chloral Betaine: May enhance the adverse/toxic effect of Anticholinergic Agents. Monitor therapy
Chlormethiazole: May enhance the CNS depressant effect of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Consider therapy modification
Chlorphenesin Carbamate: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy
Cimetropium: Anticholinergic Agents may enhance the anticholinergic effect of Cimetropium. Avoid combination
CloZAPine: May diminish the therapeutic effect of Phenylephrine (Systemic). Monitor therapy
CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants. Monitor therapy
Cobicistat: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy
Cocaine: May enhance the hypertensive effect of Sympathomimetics. Management: Consider alternatives to use of this combination when possible. Monitor closely for substantially increased blood pressure or heart rate and for any evidence of myocardial ischemia with concurrent use. Consider therapy modification
CYP2B6 Inducers (Moderate): May decrease the serum concentration of CYP2B6 Substrates. Monitor therapy
CYP2D6 Inhibitors (Moderate): May decrease the metabolism of CYP2D6 Substrates. Monitor therapy
CYP2D6 Inhibitors (Strong): May decrease the metabolism of CYP2D6 Substrates. Consider therapy modification
Dabrafenib: May decrease the serum concentration of CYP2B6 Substrates. Monitor therapy
Dapoxetine: May enhance the adverse/toxic effect of Serotonin Modulators. Avoid combination
Darunavir: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy
Dimethindene (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Doxofylline: Sympathomimetics may enhance the adverse/toxic effect of Doxofylline. Monitor therapy
Doxylamine: May enhance the CNS depressant effect of CNS Depressants. Management: The manufacturer of Diclegis (doxylamine/pyridoxine), intended for use in pregnancy, specifically states that use with other CNS depressants is not recommended. Monitor therapy
Dronabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (e.g., opioids, barbiturates) with concomitant use. Consider therapy modification
Eluxadoline: Anticholinergic Agents may enhance the constipating effect of Eluxadoline. Avoid combination
EPINEPHrine (Nasal): Promethazine may diminish the vasoconstricting effect of EPINEPHrine (Nasal). Monitor therapy
EPINEPHrine (Oral Inhalation): Promethazine may diminish the therapeutic effect of EPINEPHrine (Oral Inhalation). Monitor therapy
Epinephrine (Racemic): Promethazine may diminish the vasoconstricting effect of Epinephrine (Racemic). Management: Monitor for diminished vasoconstrictive effects of racemic epinephrine (e.g., diminished efficacy when used for gingival retraction). This interaction is likely of less concern in patients receiving epinephrine for other purposes (e.g., bronchodilation). Monitor therapy
EPINEPHrine (Systemic): Promethazine may diminish the vasoconstricting effect of EPINEPHrine (Systemic). Management: When vasoconstrictive effects are desired in patients receiving promethazine, consider alternatives to epinephrine. Consider use of norepinephrine or phenylephrine, and avoid epinephrine, when treating hypotension associated with promethazine overdose. Consider therapy modification
Ergot Derivatives: May enhance the hypertensive effect of Alpha1-Agonists. Ergot Derivatives may enhance the vasoconstricting effect of Alpha1-Agonists. Exceptions: Ergoloid Mesylates; Nicergoline. Avoid combination
Flunitrazepam: CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. Consider therapy modification
Gastrointestinal Agents (Prokinetic): Anticholinergic Agents may diminish the therapeutic effect of Gastrointestinal Agents (Prokinetic). Monitor therapy
Glucagon: Anticholinergic Agents may enhance the adverse/toxic effect of Glucagon. Specifically, the risk of gastrointestinal adverse effects may be increased. Avoid combination
Glycopyrrolate (Oral Inhalation): Anticholinergic Agents may enhance the anticholinergic effect of Glycopyrrolate (Oral Inhalation). Avoid combination
Guanethidine: May enhance the arrhythmogenic effect of Sympathomimetics. Guanethidine may enhance the hypertensive effect of Sympathomimetics. Monitor therapy
Highest Risk QTc-Prolonging Agents: QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying) may enhance the QTc-prolonging effect of Highest Risk QTc-Prolonging Agents. Management: Avoid such combinations when possible. Use should be accompanied by close monitoring for evidence of QT prolongation or other alterations of cardiac rhythm. Consider therapy modification
Hyaluronidase: May enhance the vasoconstricting effect of Phenylephrine (Systemic). Management: Avoid the use of hyaluronidase to enhance dispersion or absorption of phenylephrine. Use of hyaluronidase for other purposes in patients receiving phenylephrine may be considered as clinically indicated. Avoid combination
HYDROcodone: CNS Depressants may enhance the CNS depressant effect of HYDROcodone. Management: Avoid concomitant use of hydrocodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification
HydrOXYzine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Imatinib: May increase the serum concentration of CYP2D6 Substrates. Monitor therapy
Iobenguane I 123: Sympathomimetics may diminish the therapeutic effect of Iobenguane I 123. Avoid combination
Ioflupane I 123: Phenylephrine (Systemic) may diminish the diagnostic effect of Ioflupane I 123. Monitor therapy
Ipratropium (Oral Inhalation): May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination
Itopride: Anticholinergic Agents may diminish the therapeutic effect of Itopride. Monitor therapy
Kava Kava: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy
Levosulpiride: Anticholinergic Agents may diminish the therapeutic effect of Levosulpiride. Avoid combination
Linezolid: May enhance the hypertensive effect of Sympathomimetics. Management: Reduce initial doses of sympathomimetic agents, and closely monitor for enhanced pressor response, in patients receiving linezolid. Specific dose adjustment recommendations are not presently available. Consider therapy modification
Linezolid: May enhance the serotonergic effect of Serotonin Modulators. This could result in serotonin syndrome. Management: Due to a risk of serotonin syndrome/serotonin toxicity, discontinue serotonin modulators 2 weeks prior to the administration of linezolid. If urgent initiation of linezolid is needed, discontinue serotonin modulators immediately and monitor closely. Consider therapy modification
Lofexidine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Lumacaftor: May decrease the serum concentration of CYP2B6 Substrates. Monitor therapy
Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
MAO Inhibitors: May enhance the hypertensive effect of Alpha1-Agonists. While linezolid is expected to interact via this mechanism, management recommendations differ from other monoamine oxidase inhibitors. Refer to linezolid specific monographs for details. Exceptions: Linezolid; Tedizolid. Avoid combination
Metaxalone: May enhance the serotonergic effect of Serotonin Modulators. This could result in serotonin syndrome. Monitor therapy
Methotrimeprazine: May enhance the CNS depressant effect of CNS Depressants. CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. Consider therapy modification
Methylene Blue: May enhance the serotonergic effect of Serotonin Modulators. This could result in serotonin syndrome. Avoid combination
Methylphenidate: May enhance the adverse/toxic effect of Serotonin Modulators. Specifically, the risk of serotonin syndrome or serotonin toxicity may be increased. Monitor therapy
Metoclopramide: May enhance the adverse/toxic effect of Promethazine. Avoid combination
MetyroSINE: May enhance the adverse/toxic effect of Promethazine. Monitor therapy
Mianserin: May enhance the anticholinergic effect of Anticholinergic Agents. Monitor therapy
MiFEPRIStone: May enhance the QTc-prolonging effect of QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying). Management: Though the drugs listed here have uncertain QT-prolonging effects, they all have some possible association with QT prolongation and should generally be avoided when possible. Consider therapy modification
Minocycline: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Mirabegron: Anticholinergic Agents may enhance the adverse/toxic effect of Mirabegron. Monitor therapy
Mirtazapine: CNS Depressants may enhance the CNS depressant effect of Mirtazapine. Monitor therapy
Moderate Risk QTc-Prolonging Agents: QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying) may enhance the QTc-prolonging effect of Moderate Risk QTc-Prolonging Agents. Monitor therapy
Nabilone: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Nitroglycerin: Anticholinergic Agents may decrease the absorption of Nitroglycerin. Specifically, anticholinergic agents may decrease the dissolution of sublingual nitroglycerin tablets, possibly impairing or slowing nitroglycerin absorption. Monitor therapy
OnabotulinumtoxinA: Anticholinergic Agents may enhance the anticholinergic effect of OnabotulinumtoxinA. Monitor therapy
Orphenadrine: CNS Depressants may enhance the CNS depressant effect of Orphenadrine. Avoid combination
Oxatomide: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination
Oxomemazine: May enhance the CNS depressant effect of CNS Depressants. Avoid combination
OxyCODONE: CNS Depressants may enhance the CNS depressant effect of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification
Panobinostat: May increase the serum concentration of CYP2D6 Substrates. Management: Avoid concurrent use of sensitive CYP2D6 substrates when possible, particularly those substrates with a narrow therapeutic index. Consider therapy modification
Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Avoid combination
Peginterferon Alfa-2b: May decrease the serum concentration of CYP2D6 Substrates. Peginterferon Alfa-2b may increase the serum concentration of CYP2D6 Substrates. Monitor therapy
Perampanel: May enhance the CNS depressant effect of CNS Depressants. Management: Patients taking perampanel with any other drug that has CNS depressant activities should avoid complex and high-risk activities, particularly those such as driving that require alertness and coordination, until they have experience using the combination. Consider therapy modification
Perhexiline: CYP2D6 Substrates may increase the serum concentration of Perhexiline. Perhexiline may increase the serum concentration of CYP2D6 Substrates. Monitor therapy
Piribedil: CNS Depressants may enhance the CNS depressant effect of Piribedil. Monitor therapy
Potassium Chloride: Anticholinergic Agents may enhance the ulcerogenic effect of Potassium Chloride. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium chloride. Avoid combination
Potassium Citrate: Anticholinergic Agents may enhance the ulcerogenic effect of Potassium Citrate. Avoid combination
Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Monitor therapy
Pramlintide: May enhance the anticholinergic effect of Anticholinergic Agents. These effects are specific to the GI tract. Consider therapy modification
Propacetamol: May increase the serum concentration of Phenylephrine (Systemic). Management: Monitor patients closely for increased side effects of phenylephrine if propacetamol is used concomitantly. Patients with underlying blood pressure issues or arrhythmias may need closer monitoring and may warrant consideration of alternative therapies. Monitor therapy
Ramosetron: Anticholinergic Agents may enhance the constipating effect of Ramosetron. Monitor therapy
RimabotulinumtoxinB: Anticholinergic Agents may enhance the anticholinergic effect of RimabotulinumtoxinB. Monitor therapy
ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Monitor therapy
Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Monitor therapy
Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Monitor therapy
Secretin: Anticholinergic Agents may diminish the therapeutic effect of Secretin. Management: Avoid concomitant use of anticholinergic agents and secretin. Discontinue anticholinergic agents at least 5 half-lives prior to administration of secretin. Consider therapy modification
Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Monitor therapy
Serotonin Modulators: May enhance the adverse/toxic effect of other Serotonin Modulators. The development of serotonin syndrome may occur. Exceptions: Nicergoline; Tedizolid. Monitor therapy
Sodium Oxybate: May enhance the CNS depressant effect of CNS Depressants. Management: Consider alternatives to combined use. When combined use is needed, consider minimizing doses of one or more drugs. Use of sodium oxybate with alcohol or sedative hypnotics is contraindicated. Consider therapy modification
Suvorexant: CNS Depressants may enhance the CNS depressant effect of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Consider therapy modification
Sympathomimetics: May enhance the adverse/toxic effect of other Sympathomimetics. Monitor therapy
Tapentadol: May enhance the CNS depressant effect of CNS Depressants. Management: Avoid concomitant use of tapentadol and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification
Tedizolid: May enhance the serotonergic effect of Serotonin Modulators. This could result in serotonin syndrome. Monitor therapy
Tedizolid: May enhance the hypertensive effect of Sympathomimetics. Tedizolid may enhance the tachycardic effect of Sympathomimetics. Monitor therapy
Tetrahydrocannabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Avoid combination
Thiazide and Thiazide-Like Diuretics: Anticholinergic Agents may increase the serum concentration of Thiazide and Thiazide-Like Diuretics. Monitor therapy
Thiotepa: May increase the serum concentration of CYP2B6 Substrates. Monitor therapy
Tiotropium: Anticholinergic Agents may enhance the anticholinergic effect of Tiotropium. Avoid combination
Topiramate: Anticholinergic Agents may enhance the adverse/toxic effect of Topiramate. Monitor therapy
Tricyclic Antidepressants: May enhance the vasopressor effect of Alpha1-Agonists. Tricyclic Antidepressants may diminish the vasopressor effect of Alpha1-Agonists. Monitor therapy
Trimeprazine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy
Umeclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination
Zolpidem: CNS Depressants may enhance the CNS depressant effect of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Consider therapy modification
ALERT U.S. Boxed Warning
Promethazine hydrochloride should not be used in pediatric patients less than 2 years of age because of the potential for fatal respiratory depression. Postmarketing cases of respiratory depression, including fatalities, have been reported with use of promethazine hydrochloride in pediatric patients less than 2 years of age. A wide range of weight-based doses of promethazine hydrochloride have resulted in respiratory depression in these patients.
Caution should be exercised when administering promethazine hydrochloride to pediatric patients 2 years of age and older. It is recommended that the lowest effective dose of promethazine hydrochloride be used in pediatric patients 2 years of age and older and concomitant administration of other drugs with respiratory depressant effects be avoided.