Abnormal elevation of serum potassium levels (≥5.5 mEq/L) can occur with all potassium-conserving diuretic combinations, including hydrochlorothiazide/triamterene. Hyperkalemia is more likely to occur in patients with renal impairment and diabetes (even without evidence of renal impairment), or elderly or severely ill patients. Because uncorrected hyperkalemia may be fatal, serum potassium levels must be monitored at frequent intervals, especially in patients first receiving hydrochlorothiazide/triamterene, when dosages are changed, or with any illness that may influence renal function.
Hypertension, edema: Oral:
Hydrochlorothiazide 25 mg/triamterene 37.5 mg: 1 to 2 tablets/capsules once daily.
Hydrochlorothiazide 25 mg/triamterene 50 mg: 1 to 2 capsules once daily.
Hydrochlorothiazide 50 mg/triamterene 75 mg: 1 tablet daily.
Meniere disease, chronic management (off-label use):
Note: Reserve pharmacotherapy for patients in whom lifestyle modifications do not result in sufficient response. Provide as-needed vestibular suppressants and antiemetics for acute relief of vertigo (Ref).
Oral: Hydrochlorothiazide 25 mg/triamterene 37.5 mg: 1 tablet or capsule once daily (Ref). May discontinue after 6 months of prolonged control (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in the manufacturer’s labeling. Contraindicated in patients with anuria, acute and chronic renal insufficiency, or significant renal impairment.
There are no dosage adjustments provided in the manufacturer’s labeling; use with caution and monitor for precipitation of hepatic coma.
Refer to adult dosing; use with caution.
The following adverse drug reactions are derived from product labeling unless otherwise specified. Also see individual agents.
Frequency not defined:
Cardiovascular: Cardiac arrhythmia, orthostatic hypotension
Dermatologic: Skin rash, urticaria
Endocrine & metabolic: Acidosis, diabetes mellitus, hypercalcemia, hyperglycemia, hyperkalemia, hyperuricemia, hypochloremia, hypokalemia
Gastrointestinal: Abdominal pain, constipation, diarrhea, nausea, pancreatitis, sialadenitis, vomiting, xerostomia
Genitourinary: Glycosuria, impotence, urine sedimentation abnormality
Hematologic & oncologic: Leukopenia, megaloblastic anemia, purpuric disease, thrombocytopenia
Hepatic: Jaundice, liver enzyme disorder
Hypersensitivity: Anaphylaxis
Nervous system: Asthenia, dizziness, fatigue, headache
Neuromuscular & skeletal: Lupus-like syndrome (subacute cutaneous), muscle cramps
Renal: Acute kidney injury, increased blood urea nitrogen, increased serum creatinine, interstitial nephritis, nephrolithiasis
Postmarketing:
Dermatologic: Malignant neoplasm of lip (Friedman 2012), skin photosensitivity (Friedman 2012)
Endocrine & metabolic: Hyponatremia (Roberts 1984), nephrogenic diabetes insipidus (Macleod 1981), pseudoporphyria (Motley 1990)
Ophthalmic: Angle-closure glaucoma (Murphy 2016)
Hypersensitivity to hydrochlorothiazide, triamterene, sulfonamide-derived drugs, or any component of the formulation; anuria; acute and chronic renal insufficiency or significant renal impairment; patients receiving other potassium-sparing diuretics, potassium-containing salt substitutes, or potassium supplements (except in severe cases of hypokalemia); preexisting hyperkalemia.
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Note: Although the FDA-approved product labeling states this medication is contraindicated in patients with hypersensitivity to sulfonamide-containing drugs, the scientific basis of this cross-sensitivity has been challenged.
Canadian labeling: Additional contraindications (not in US labeling): Severe or progressive hepatic dysfunction
Concerns related to adverse effects:
• Electrolyte disturbances: Hypokalemia, hypochloremic alkalosis, and hyponatremia may occur with hydrochlorothiazide.
• Gout: In certain patients with a history of gout, a familial predisposition to gout, or chronic renal failure, gout can be precipitated by hydrochlorothiazide. This risk may be increased with doses ≥25 mg (Gurwitz 1997).
• Hyperkalemia: Hyperkalemia can occur with triamterene; patients at risk include those with renal impairment, diabetes (even without evidence of renal impairment), the elderly, and the severely ill. Serum potassium levels must be monitored at frequent intervals especially in patients first receiving hydrochlorothiazide/triamterene, when dosages are changed, or with any illness that may influence renal function. Avoid potassium supplements (except in severe cases of hypokalemia), potassium-containing salt substitutes, a diet rich in potassium, or other drugs that can cause hyperkalemia. Discontinue immediately if hyperkalemia develops. Patients who are severely ill may develop respiratory or metabolic acidosis which may be associated with rapid elevations in serum potassium concentrations; avoid use in these patients.
• Hypersensitivity reactions: Hypersensitivity reactions may occur with hydrochlorothiazide. Risk is increased in patients with a history of allergy or bronchial asthma.
• Ocular effects: Hydrochlorothiazide may cause acute transient myopia and acute angle-closure glaucoma, typically occurring within hours to weeks following initiation; discontinue therapy immediately in patients with acute decreases in visual acuity or ocular pain. Additional treatments may be needed if uncontrolled intraocular pressure persists. Risk factors may include a history of sulfonamide or penicillin allergy.
• Photosensitivity: Photosensitization may occur.
• Skin cancer, nonmelanoma: Prolonged use (≥3 years) may increase the risk for squamous cell carcinoma up to 4 times and increase the risk for basal cell carcinoma up to 1.25 times compared to patients not treated with hydrochlorothiazide (Pedersen 2018; Pottegård 2017).
• Sulfonamide (“sulfa”) allergy: The FDA-approved product labeling for many medications containing a sulfonamide chemical group includes a broad contraindication in patients with a prior allergic reaction to sulfonamides. There is a potential for cross-reactivity between members of a specific class (eg, two antibiotic sulfonamides). However, concerns for cross-reactivity have previously extended to all compounds containing the sulfonamide structure (SO2NH2). An expanded understanding of allergic mechanisms indicates cross-reactivity between antibiotic sulfonamides and nonantibiotic sulfonamides may not occur or at the very least this potential is extremely low (Brackett 2004; Johnson 2005; Slatore 2004; Tornero 2004). In particular, mechanisms of cross-reaction due to antibody production (anaphylaxis) are unlikely to occur with nonantibiotic sulfonamides. T-cell-mediated (type IV) reactions (eg, maculopapular rash) are less well understood and it is not possible to completely exclude this potential based on current insights. In cases where prior reactions were severe (Stevens-Johnson syndrome/TEN), some clinicians choose to avoid exposure to these classes.
Disease-related concerns:
• Bariatric surgery: Dehydration: Avoid diuretics in the immediate postoperative period after bariatric surgery; electrolyte disturbances and dehydration may occur. Diuretics may be resumed, if indicated, once oral fluid intake goals are met (Ziegler 2009).
• Diabetes: Use with caution in patients with prediabetes or diabetes mellitus; may alter glycemic control.
• Hepatic impairment: Use caution in patients with severe hepatic impairment. In progressive or severe liver disease, avoid electrolyte and acid/base imbalances that might lead to hepatic encephalopathy/coma.
• Hypercalcemia: Thiazide diuretics may decrease renal calcium excretion; consider avoiding use in patients with hypercalcemia.
• Hypercholesterolemia: Use with caution in patients with moderate or high cholesterol concentrations; increased cholesterol and triglyceride levels have been reported with thiazides.
• Kidney stones: Use triamterene with caution in patients with kidney stones.
• Parathyroid disease: Thiazide diuretics reduce calcium excretion; pathologic changes in the parathyroid glands with hypercalcemia and hypophosphatemia have been observed with prolonged use. Thiazides should be discontinued prior to tests for parathyroid function.
• Renal impairment: Cumulative effects of hydrochlorothiazide may develop, including azotemia, in patients with impaired renal function. Avoid hydrochlorothiazide in severe renal disease (ineffective). Triamterene may cause hyperkalemia in patients with renal impairment.
• Systemic lupus erythematosus (SLE): Hydrochlorothiazide may cause SLE exacerbation or activation.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Capsule, Oral:
Generic: Hydrochlorothiazide 25 mg and triamterene 37.5 mg
Tablet, Oral:
Maxzide-25: Hydrochlorothiazide 25 mg and triamterene 37.5 mg [DSC] [scored; contains fd&c blue #1 (brilliant blue), quinoline yellow (d&c yellow #10)]
Maxzide: Hydrochlorothiazide 50 mg and triamterene 75 mg [DSC] [scored; contains quinoline yellow (d&c yellow #10)]
Generic: Hydrochlorothiazide 25 mg and triamterene 37.5 mg, Hydrochlorothiazide 50 mg and triamterene 75 mg
Yes
Capsules (Triamterene-HCTZ Oral)
37.5-25 mg (per each): $0.37 - $1.40
Tablets (Triamterene-HCTZ Oral)
37.5-25 mg (per each): $0.36 - $0.39
75-50 mg (per each): $0.92 - $1.11
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral:
Generic: Hydrochlorothiazide 25 mg and triamterene 50 mg
Oral: Administer without regard to meals.
Hypertension, edema: Treatment of hypertension or edema (not recommended for initial treatment) when hypokalemia has developed on hydrochlorothiazide alone or when the development of hypokalemia must be avoided.
Meniere disease
Dyazide may be confused with diazoxide, Dynacin
Maxzide may be confused with Maxidex
Beers Criteria: Diuretics (hydrochlorothiazide and triamterene) are identified in the Beers Criteria as potentially inappropriate medications to be used with caution in patients 65 years and older due to the potential to cause or exacerbate syndrome of inappropriate antidiuretic hormone secretion (SIADH) or hyponatremia; monitor sodium concentration closely when initiating or adjusting the dose in older adults (Beers Criteria [AGS 2023]).
Maxzide [US, multiple international markets] may be confused with Microzide brand name for gliclazide [Jordan, Qatar] and hydroCHLOROthiazide [Puerto Rico]
Refer to individual components.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Agents with Clinically Relevant Anticholinergic Effects: May increase serum concentration of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Ajmaline: Sulfonamides may increase adverse/toxic effects of Ajmaline. Specifically, the risk for cholestasis may be increased. Risk C: Monitor
Alcohol (Ethyl): May increase orthostatic hypotensive effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Alfuzosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Aliskiren: Potassium-Sparing Diuretics may increase hyperkalemic effects of Aliskiren. Risk C: Monitor
Allopurinol: Thiazide and Thiazide-Like Diuretics may increase hypersensitivity effects of Allopurinol. Risk C: Monitor
Amifostine: Blood Pressure Lowering Agents may increase hypotensive effects of Amifostine. Management: When used at chemotherapy doses, hold blood pressure lowering medications for 24 hours before amifostine administration. If blood pressure lowering therapy cannot be held, do not administer amifostine. Use caution with radiotherapy doses of amifostine. Risk D: Consider Therapy Modification
Aminolevulinic Acid (Systemic): Photosensitizing Agents may increase photosensitizing effects of Aminolevulinic Acid (Systemic). Risk X: Avoid
Aminolevulinic Acid (Topical): Photosensitizing Agents may increase photosensitizing effects of Aminolevulinic Acid (Topical). Risk C: Monitor
Ammonium Chloride: Potassium-Sparing Diuretics may increase adverse/toxic effects of Ammonium Chloride. Specifically the risk of systemic acidosis. Risk C: Monitor
Amphetamines: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Angiotensin II Receptor Blockers: Potassium-Sparing Diuretics may increase hyperkalemic effects of Angiotensin II Receptor Blockers. Risk C: Monitor
Angiotensin-Converting Enzyme Inhibitors: Potassium-Sparing Diuretics may increase hyperkalemic effects of Angiotensin-Converting Enzyme Inhibitors. Risk C: Monitor
Angiotensin-Converting Enzyme Inhibitors: Thiazide and Thiazide-Like Diuretics may increase hypotensive effects of Angiotensin-Converting Enzyme Inhibitors. Thiazide and Thiazide-Like Diuretics may increase nephrotoxic effects of Angiotensin-Converting Enzyme Inhibitors. Risk C: Monitor
Antidiabetic Agents: Hyperglycemia-Associated Agents may decrease therapeutic effects of Antidiabetic Agents. Risk C: Monitor
Antidiabetic Agents: Thiazide and Thiazide-Like Diuretics may decrease therapeutic effects of Antidiabetic Agents. Risk C: Monitor
Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may increase hypotensive effects of Antipsychotic Agents (Second Generation [Atypical]). Risk C: Monitor
Arginine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Arimoclomol: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Risk C: Monitor
Arsenic Trioxide: Thiazide and Thiazide-Like Diuretics may increase hypotensive effects of Arsenic Trioxide. Thiazide and Thiazide-Like Diuretics may increase QTc-prolonging effects of Arsenic Trioxide. Management: When possible, avoid concurrent use of arsenic trioxide with drugs that can cause electrolyte abnormalities, such as the thiazide and thiazide-like diuretics. Risk D: Consider Therapy Modification
Barbiturates: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Benperidol: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Beta2-Agonists: May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Bile Acid Sequestrants: May decrease absorption of Thiazide and Thiazide-Like Diuretics. Management: Separate administration of bile acid sequestrants and oral thiazide diuretics by at least 4 hours. Monitor for decreased therapeutic effects of thiazide diuretics if coadministered with a bile acid sequestrant. Risk D: Consider Therapy Modification
Brigatinib: May decrease antihypertensive effects of Antihypertensive Agents. Brigatinib may increase bradycardic effects of Antihypertensive Agents. Risk C: Monitor
Brimonidine (Topical): May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Bromperidol: May decrease hypotensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase hypotensive effects of Bromperidol. Risk X: Avoid
Calcium Salts: Thiazide and Thiazide-Like Diuretics may increase serum concentration of Calcium Salts. Risk C: Monitor
Cardiac Glycosides: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Cardiac Glycosides. Specifically, cardiac glycoside toxicity may be enhanced by the hypokalemic and hypomagnesemic effect of thiazide diuretics. Risk C: Monitor
Corticosteroids (Systemic): May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
CycloPHOSphamide: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of CycloPHOSphamide. Specifically, granulocytopenia may be enhanced. Risk C: Monitor
CycloSPORINE (Systemic): Potassium-Sparing Diuretics may increase hyperkalemic effects of CycloSPORINE (Systemic). Risk X: Avoid
Desmopressin: Hyponatremia-Associated Agents may increase hyponatremic effects of Desmopressin. Risk C: Monitor
Dexketoprofen: May increase adverse/toxic effects of Sulfonamides. Risk C: Monitor
Dexmethylphenidate: May decrease therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Diacerein: May increase therapeutic effects of Diuretics. Specifically, the risk for dehydration or hypokalemia may be increased. Risk C: Monitor
Diazoxide Choline: May increase adverse/toxic effects of Thiazide and Thiazide-Like Diuretics. Specifically, the hyperglycemic and hyperuricemic effects may be increased. Risk C: Monitor
Diazoxide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Diazoxide: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Diazoxide. Risk C: Monitor
Dichlorphenamide: Thiazide and Thiazide-Like Diuretics may increase hypokalemic effects of Dichlorphenamide. Risk C: Monitor
Digitoxin: Potassium-Sparing Diuretics may increase adverse/toxic effects of Digitoxin. Potassium-Sparing Diuretics may decrease therapeutic effects of Digitoxin. Risk C: Monitor
Dofetilide: HydroCHLOROthiazide may increase QTc-prolonging effects of Dofetilide. HydroCHLOROthiazide may increase serum concentration of Dofetilide. Risk X: Avoid
Drospirenone-Containing Products: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
DULoxetine: Blood Pressure Lowering Agents may increase hypotensive effects of DULoxetine. Risk C: Monitor
EPINEPHrine (Systemic): Diuretics may increase arrhythmogenic effects of EPINEPHrine (Systemic). Diuretics may decrease vasopressor effects of EPINEPHrine (Systemic). Risk C: Monitor
Fedratinib: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Risk C: Monitor
Fexinidazole: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Management: Avoid use of fexinidazole with OCT2 substrates when possible. If combined, monitor for increased OCT2 substrate toxicities. Risk D: Consider Therapy Modification
Finerenone: Potassium-Sparing Diuretics may increase hyperkalemic effects of Finerenone. Risk C: Monitor
Flunarizine: May increase therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Givinostat: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Risk C: Monitor
Heparin: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Heparins (Low Molecular Weight): May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Herbal Products with Blood Pressure Increasing Effects: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Herbal Products with Blood Pressure Lowering Effects: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Hypotension-Associated Agents: Blood Pressure Lowering Agents may increase hypotensive effects of Hypotension-Associated Agents. Risk C: Monitor
Iloperidone: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Indomethacin: Triamterene may increase adverse/toxic effects of Indomethacin. Specifically, the risk for renal failure and hyperkalemia may be increased. Management: Consider alternatives to concomitant treatment with triamterene and indomethacin. If the combination cannot be avoided, monitor for development of renal failure and hyperkalemia. Risk D: Consider Therapy Modification
Indoramin: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Ipragliflozin: May increase adverse/toxic effects of Thiazide and Thiazide-Like Diuretics. Specifically, the risk for intravascular volume depletion may be increased. Risk C: Monitor
Isocarboxazid: May increase hypotensive effects of Diuretics. Risk X: Avoid
Ivabradine: Thiazide and Thiazide-Like Diuretics may increase arrhythmogenic effects of Ivabradine. Risk C: Monitor
Levodopa-Foslevodopa: Blood Pressure Lowering Agents may increase hypotensive effects of Levodopa-Foslevodopa. Risk C: Monitor
Levosulpiride: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Levosulpiride. Risk X: Avoid
Licorice: May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Lithium: Thiazide and Thiazide-Like Diuretics may decrease excretion of Lithium. Management: Reduce the lithium dose if coadministered with thiazide or thiazide-like diuretics. Monitor serum lithium levels during coadministration with thiazide and thiazide-like diuretics. Risk D: Consider Therapy Modification
Loop Diuretics: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Lormetazepam: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Mecamylamine: Thiazide and Thiazide-Like Diuretics may increase adverse/toxic effects of Mecamylamine. Management: Consider avoiding the use of mecamylamine and thiazide diuretics. If combined, mecamylamine prescribing information suggests reducing the mecamylamine dose by 50% in order to avoid excessive hypotension. Risk D: Consider Therapy Modification
Metergoline: May decrease antihypertensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase orthostatic hypotensive effects of Metergoline. Risk C: Monitor
Methenamine: Thiazide and Thiazide-Like Diuretics may decrease therapeutic effects of Methenamine. Risk C: Monitor
Methotrexate: HydroCHLOROthiazide may increase nephrotoxic effects of Methotrexate. Risk C: Monitor
Methoxsalen (Systemic): Photosensitizing Agents may increase photosensitizing effects of Methoxsalen (Systemic). Risk C: Monitor
Methylphenidate: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Molsidomine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Multivitamins/Fluoride (with ADE): May increase hypercalcemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Multivitamins/Minerals (with ADEK, Folate, Iron): Thiazide and Thiazide-Like Diuretics may increase hypercalcemic effects of Multivitamins/Minerals (with ADEK, Folate, Iron). Risk C: Monitor
Multivitamins/Minerals (with AE, No Iron): Thiazide and Thiazide-Like Diuretics may increase serum concentration of Multivitamins/Minerals (with AE, No Iron). Specifically, thiazide diuretics may decrease the excretion of calcium, and continued concomitant use can also result in metabolic alkalosis. Risk C: Monitor
Naftopidil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Neuromuscular-Blocking Agents (Nondepolarizing): Thiazide and Thiazide-Like Diuretics may increase neuromuscular-blocking effects of Neuromuscular-Blocking Agents (Nondepolarizing). Risk C: Monitor
Nicergoline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicorandil: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Nicorandil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nitroprusside: Blood Pressure Lowering Agents may increase hypotensive effects of Nitroprusside. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents (Topical): May decrease therapeutic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents: May decrease therapeutic effects of Thiazide and Thiazide-Like Diuretics. Thiazide and Thiazide-Like Diuretics may increase nephrotoxic effects of Nonsteroidal Anti-Inflammatory Agents. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Nonsteroidal Anti-Inflammatory Agents may decrease antihypertensive effects of Potassium-Sparing Diuretics. Risk C: Monitor
Obinutuzumab: May increase hypotensive effects of Blood Pressure Lowering Agents. Management: Consider temporarily withholding blood pressure lowering medications beginning 12 hours prior to obinutuzumab infusion and continuing until 1 hour after the end of the infusion. Risk D: Consider Therapy Modification
Opioid Agonists: May increase adverse/toxic effects of Diuretics. Opioid Agonists may decrease therapeutic effects of Diuretics. Risk C: Monitor
Palopegteriparatide: Thiazide and Thiazide-Like Diuretics may increase therapeutic effects of Palopegteriparatide. Thiazide and Thiazide-Like Diuretics may decrease therapeutic effects of Palopegteriparatide. Risk C: Monitor
Pentoxifylline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Perazine: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Pholcodine: Blood Pressure Lowering Agents may increase hypotensive effects of Pholcodine. Risk C: Monitor
Phosphodiesterase 5 Inhibitors: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Piperacillin: May increase hypokalemic effects of Diuretics. Risk C: Monitor
Polyethylene Glycol-Electrolyte Solution: Diuretics may increase nephrotoxic effects of Polyethylene Glycol-Electrolyte Solution. Risk C: Monitor
Porfimer: Photosensitizing Agents may increase photosensitizing effects of Porfimer. Risk X: Avoid
Potassium Salts: May increase hyperkalemic effects of Triamterene. Risk X: Avoid
Potassium-Sparing Diuretics: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk X: Avoid
Pramipexole: Triamterene may increase hypotensive effects of Pramipexole. Triamterene may increase serum concentration of Pramipexole. Risk C: Monitor
Prazosin: Antihypertensive Agents may increase hypotensive effects of Prazosin. Risk C: Monitor
Promazine: Thiazide and Thiazide-Like Diuretics may increase QTc-prolonging effects of Promazine. Risk X: Avoid
Prostacyclin Analogues: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Quinagolide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Reboxetine: May increase hypokalemic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Selective Serotonin Reuptake Inhibitor: May increase hyponatremic effects of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Silodosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Sodium Phosphates: Diuretics may increase nephrotoxic effects of Sodium Phosphates. Specifically, the risk of acute phosphate nephropathy may be enhanced. Risk C: Monitor
Sotagliflozin: HydroCHLOROthiazide may decrease therapeutic effects of Sotagliflozin. Sotagliflozin may decrease serum concentration of HydroCHLOROthiazide. Risk C: Monitor
Tacrolimus (Systemic): Potassium-Sparing Diuretics may increase hyperkalemic effects of Tacrolimus (Systemic). Risk C: Monitor
Tafenoquine: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Management: Avoid use of OCT2 substrates with tafenoquine, and if the combination cannot be avoided, monitor closely for evidence of toxicity of the OCT2 substrate and consider a reduced dose of the OCT2 substrate according to that substrate's labeling. Risk D: Consider Therapy Modification
Terazosin: Antihypertensive Agents may increase hypotensive effects of Terazosin. Risk C: Monitor
Tolvaptan: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Topiramate: Thiazide and Thiazide-Like Diuretics may increase hypokalemic effects of Topiramate. Thiazide and Thiazide-Like Diuretics may increase serum concentration of Topiramate. Risk C: Monitor
Toremifene: Thiazide and Thiazide-Like Diuretics may increase hypercalcemic effects of Toremifene. Risk C: Monitor
Trimethoprim: May increase hyperkalemic effects of Potassium-Sparing Diuretics. Risk C: Monitor
Urapidil: Antihypertensive Agents may increase hypotensive effects of Urapidil. Risk C: Monitor
Verteporfin: Photosensitizing Agents may increase photosensitizing effects of Verteporfin. Risk C: Monitor
Vimseltinib: May increase serum concentration of OCT2 Substrates (Clinically Relevant with Inhibitors). Management: Avoid concomitant use of vimseltinib and OCT2 substrates when possible. If combined, monitor for increased effects and toxicities of the OCT2 substrate and consider dose adjustments. Risk D: Consider Therapy Modification
Vitamin D Analogs: Thiazide and Thiazide-Like Diuretics may increase hypercalcemic effects of Vitamin D Analogs. Risk C: Monitor
See individual agents.
Hydrochlorothiazide and triamterene cross the placenta.
Refer to individual monographs for additional information.
Hydrochlorothiazide is present in breast milk; excretion of triamterene is not known.
Breastfeeding is not recommended by the manufacturer. Refer to individual monographs for additional information.
BP, serum electrolytes, BUN, creatinine, LFTs, signs of hyperkalemia.
Hydrochlorothiazide: Inhibits sodium reabsorption in the distal tubules causing increased excretion of sodium and water as well as potassium and hydrogen ions.
Triamterene: Blocks epithelial sodium channels in the late distal convoluted tubule (DCT) and collecting duct which inhibits sodium reabsorption from the lumen. This effectively reduces intracellular sodium, decreasing the function of Na+/K+ ATPase, leading to potassium retention and decreased calcium, magnesium, and hydrogen excretion. As sodium uptake capacity in the DCT/collecting duct is limited, the natriuretic, diuretic, and antihypertensive effects are generally considered weak.
See individual agents.