Triamterene and Hydrochlorothiazide 37.5 mg; 25 mg Capsule, 100-count
🆔 Identity & classification
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🏷️ RxNorm drug class
This medicine belongs to the Potassium-sparing Diuretic class.
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🏭 Manufacturer & labeler
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🩺 Clinical
The combination of triamterene and hydrochlorothiazide is used to treat high blood pressure and edema (fluid retention; excess fluid held in body tissues) in patients who have lower amounts of potassium in their bodies or for whom low potassium levels in the body could be dangerous. The combination of triamterene and hydrochlorothiazide is in a class of medications called diuretics ('water pills'). They work by causing the kidneys to get rid of unneeded water and salt from the body into the urine. High blood pressure is a common condition, and when not treated it can cause damage to the brain,...
Read the full MedlinePlus article ↗- Great question. Hydrochlorothiazide on its own works well for blood pressure and fluid retention, but it tends to flush out potassium along with the water — and low potassium can c...
- Why am I on this combination instead of just a regular water pill?
- Most people notice things like mild nausea, dizziness, headache, or muscle cramps, especially early on. You might also feel more tired or notice your urine looks a different color...
- What side effects should I actually watch out for day to day?
Patient education
Supplement & herbal interactions
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Ask a licensed pharmacist directly — free, answered by our team.
💊 What it looks like
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
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Anhydrous lactose is a milk sugar with no water content. It acts as a filler and binder in tablets and capsules, adding bulk and helping ingredients stick together.
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A weak organic acid derived from citrus fruits or made through fermentation. It works as a buffer to control pH, a preservative to extend shelf life, and a flavoring agent in medications.
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A synthetic yellow dye used to color medicines. It helps make tablets, capsules, and liquids visually distinct so patients can easily identify their medication.
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FD&C Blue No. 1 is a synthetic blue dye approved for use in foods and medicines. It serves as a colorant to give the medication its distinctive appearance and help with product identification.
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A synthetic blue dye approved by the FDA for use in medications and foods. It serves as a colorant to make pills and liquids visually distinct and easier to identify.
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UNII WZB9127XOA
A synthetic red dye used to color medications and make them easier to identify. It serves as a colorant in tablets, capsules, and liquid formulations.
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A dark iron oxide compound that gives medicines their black or dark color. It's used as a colorant in tablets and capsules to help identify the product and make it visually distinctive.
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UNII 2G86QN327L
Gelatin is a protein derived from animal collagen, commonly used in medicines as a gelling agent and capsule material. It helps create soft or hard capsule shells that hold and release medication, and can also thicken liquid formulations.
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Glycine is an amino acid used in medicines as a buffer to help stabilize pH and improve taste. It may also serve as a filler or binder to give the product proper form and consistency.
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UNII 70097M6I30
Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
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UNII 6OZP39ZG8H
Polysorbate 80 is a synthetic emulsifier derived from sorbitol and oleic acid. It helps mix oil and water-based ingredients together in medications and improves how the product disperses in the body.
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UNII FZ989GH94E
Povidone is a synthetic polymer made from a plastic-like material. It acts as a binder to hold tablet ingredients together and as a disintegrant to help the tablet break apart in your stomach so the medicine can be absorbed.
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Propylene glycol is a clear liquid derived from petroleum or vegetable sources. It acts as a solvent, humectant, and preservative in medicines, helping dissolve active ingredients and maintain product stability.
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UNII 46N107B71O
Shellac is a natural resin secreted by the lac beetle. It's used as a coating on tablets and capsules to control how quickly the medicine dissolves and to improve appearance and stability.
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UNII 5856J3G2A2
A starch-based powder made from potatoes and processed with sodium. It acts as a disintegrant, helping the tablet or capsule break apart quickly in the stomach so the medicine can be absorbed.
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UNII O8232NY3SJ
A plant-based carbohydrate derived from corn kernels. It acts as a filler to add bulk, a binder to hold ingredients together, and a disintegrant to help the tablet break apart in your stomach for absorption.
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UNII 15FIX9V2JP
Titanium dioxide is a bright white mineral powder commonly used as a colorant and opacifying agent. It makes pills and tablets white or lighter in color and helps make coatings non-transparent.
17 inactive ingredients listed in the exact product block matched to this NDC.
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ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
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💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · quarterly | No Part D plan price is available for this NDC in our data. | |
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🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 00781-2074-01 | Sandoz | 100 capsules | $0.122 | AB | Availability likely | — |
| Triamterene And Hydrochlorothiazide 37.5 mg/1; 25 mg 62135-0529-90 | Chartwell | 90 capsules | $0.122 | AB | Availability likely | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 72578-0090-01 | Viona | 100 capsules | $0.122 | AB | Availability likely | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 33342-0467-11 | Macleods | 100 capsules | — | — | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 50090-2028-00 | A-S | 30 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 50090-6944-00 | A-S | 90 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 50090-7437-00 | A-S | 30 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 50090-7438-00 | A-S | 90 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 51655-0722-52 | Northwind | 30 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 60760-0783-90 | St. | 90 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 63187-0465-30 | Proficient | 30 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 63187-0905-30 | Proficient | 30 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mgthis 63629-8732-01 | Bryant | 100 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 68071-2533-09 | NuCare | 90 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 68071-3879-09 | NuCare | 90 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 68382-0855-01 | Zydus | 100 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 68788-8700-01 | Preferred | 100 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 70518-4270-00 | REMEDYREPACK | 90 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 70771-1474-00 | Zydus | 1000 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 71335-0504-01 | Bryant | 100 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 71335-2034-01 | Bryant | 100 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 72162-1084-06 | Bryant | 60 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 82868-0022-30 | Northwind | 30 capsules | — | AB | FDA listed | — |
| Triamterene and Hydrochlorothiazide 37.5 mg/1; 25 mg 82804-0308-30 | Proficient | 30 capsules | — | AB | FDA listed | — |
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⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
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📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 63629-8732-01 You're viewing this | 100 CAPSULE in 1 BOTTLE (63629-8732-1) | 1997-06-05 | Active |
🧭 About this NDC listing & data coverage
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| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
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📄 Full prescribing information FDA SPL
🚨 Boxed Warning ▾
Hyperkalemia Abnormal elevation of serum potassium levels (≥5.5 mEq/liter) can occur with all potassium-sparing diuretic combinations, including triamterene and hydrochlorothiazide. Hyperkalemia is more likely to occur in patients with renal impairment and diabetes (even without evidence of renal impairment) and in the elderly or severely ill. Since uncorrected hyperkalemia may be fatal, serum potassium levels must be monitored at frequent intervals especially in patients first receiving triamterene and hydrochlorothiazide, when dosages are changed, or with any illness that may influence renal function.
🎯 Indications and Usage ▾
INDICATIONS AND USAGE This fixed combination drug is not indicated for the initial therapy of edema or hypertension except in individuals in whom the development of hypokalemia cannot be risked. Triamterene and hydrochlorothiazide is indicated for the treatment of hypertension or edema in patients who develop hypokalemia on hydrochlorothiazide alone. Triamterene and hydrochlorothiazide is also indicated for those patients who require a thiazide diuretic and in whom the development of hypokalemia cannot be risked.
Triamterene and hydrochlorothiazide may be used alone or as an adjunct to other antihypertensive drugs, such as beta-blockers. Since triamterene and hydrochlorothiazide may enhance the action of these agents, dosage adjustments may be necessary. Usage in Pregnancy The routine use of diuretics in an otherwise healthy woman is inappropriate and exposes mother and fetus to unnecessary hazard.
Diuretics do not prevent development of toxemia of pregnancy, and there is no satisfactory evidence that they are useful in the treatment of developed toxemia. Edema during pregnancy may arise from pathological causes or from the physiologic and mechanical consequences of pregnancy. Diuretics are indicated in pregnancy when edema is due to pathologic causes, just as they are in the absence of pregnancy.
Dependent edema in pregnancy resulting from restriction of venous return by the expanded uterus is properly treated through elevation of the lower extremities and use of support hose; use of diuretics to lower intravascular volume in this case is illogical and unnecessary. There is hypervolemia during normal pregnancy which is harmful to neither the fetus nor the mother (in the absence of cardiovascular disease), but which is associated with edema, including generalized edema in the majority of pregnant women. If this edema produces discomfort, increased recumbency will often provide relief.
In rare instances this edema may cause extreme discomfort which is not relieved by rest. In these cases, a short course of diuretics may provide relief and may be appropriate.
⏱️ Dosage and Administration ▾
DOSAGE AND ADMINISTRATION The usual dose of triamterene and hydrochlorothiazide capsules is one or two capsules given once daily, with appropriate monitoring of serum potassium and of the clinical effect (see WARNINGS, Hyperkalemia ).
⛔ Contraindications ▾
CONTRAINDICATIONS Antikaliuretic Therapy and Potassium Supplementation Triamterene and hydrochlorothiazide should not be given to patients receiving other potassium-sparing agents such as spironolactone, amiloride, or other formulations containing triamterene. Concomitant potassium-containing salt substitutes should also not be used. Potassium supplementation should not be used with triamterene and hydrochlorothiazide except in severe cases of hypokalemia.
Such concomitant therapy can be associated with rapid increases in serum potassium levels. If potassium supplementation is used, careful monitoring of the serum potassium level is necessary. Impaired Renal Function Triamterene and hydrochlorothiazide is contraindicated in patients with anuria, acute and chronic renal insufficiency, or significant renal impairment.
Hypersensitivity Hypersensitivity to either drug in the preparation or to other sulfonamide-derived drugs is a contraindication. Hyperkalemia Triamterene and hydrochlorothiazide should not be used in patients with pre-existing elevated serum potassium.
⚠️ Warnings ▾
WARNINGS Hyperkalemia Abnormal elevation of serum potassium levels (≥5.5 mEq/liter) can occur with all potassium-sparing diuretic combinations, including triamterene and hydrochlorothiazide. Hyperkalemia is more likely to occur in patients with renal impairment and diabetes (even without evidence of renal impairment) and in the elderly or severely ill. Since uncorrected hyperkalemia may be fatal, serum potassium levels must be monitored at frequent intervals especially in patients first receiving triamterene and hydrochlorothiazide, when dosages are changed, or with any illness that may influence renal function.
If hyperkalemia is suspected (warning signs include paresthesias, muscular weakness, fatigue, flaccid paralysis of the extremities, bradycardia, and shock), an electrocardiogram (ECG) should be obtained. However, it is important to monitor serum potassium levels because hyperkalemia may not be associated with ECG changes. If hyperkalemia is present, triamterene and hydrochlorothiazide should be discontinued immediately and a thiazide alone should be substituted.
If the serum potassium exceeds 6.5 mEq/L, more vigorous therapy is required. The clinical situation dictates the procedures to be employed. These include the intravenous administration of calcium chloride solution, sodium bicarbonate solution, and/or the oral or parenteral administration of glucose with a rapid-acting insulin preparation.
Cationic exchange resins such as sodium polystyrene sulfonate may be orally or rectally administered. Persistent hyperkalemia may require dialysis. The development of hyperkalemia associated with potassium-sparing diuretics is accentuated in the presence of renal impairment (see CONTRAINDICATIONS ).
Patients with mild renal functional impairment should not receive this drug without frequent and continuing monitoring of serum electrolytes. Cumulative drug effects may be observed in patients with impaired renal function. The renal clearances of hydrochlorothiazide and the pharmacologically active metabolite of triamterene, the sulfate ester of hydroxytriamterene, have been shown to be reduced and the plasma levels increased following administration of triamterene and hydrochlorothiazide to elderly patients and patients with impaired renal function.
Hyperkalemia has been reported in diabetic patients with the use of potassium-sparing agents even in the absence of apparent renal impairment. Accordingly, serum electrolytes must be frequently monitored if triamterene and hydrochlorothiazide is used in diabetic patients. Metabolic or Respiratory Acidosis Potassium-sparing therapy should also be avoided in severely ill patients in whom respiratory or metabolic acidosis may occur.
Acidosis may be associated with rapid elevations in serum potassium levels. If triamterene and hydrochlorothiazide is employed, frequent evaluations of acid/base balance and serum electrolytes are necessary. Acute Myopia and Secondary Angle-Closure Glaucoma Hydrochlorothiazide, a sulfonamide, can cause an idiosyncratic reaction, resulting in acute transient myopia and acute angle-closure glaucoma.
Symptoms include acute onset of decreased visual acuity or ocular pain and typically occur within hours to weeks of drug initiation. Untreated acute angle-closure glaucoma can lead to permanent vision loss. The primary treatment is to discontinue hydrochlorothiazide as rapidly as possible.
Prompt medical or surgical treatments may need to be considered if the intraocular pressure remains uncontrolled. Risk factors for developing acute angle-closure glaucoma may include a history of sulfonamide or penicillin allergy.
🤒 Adverse Reactions ▾
ADVERSE REACTIONS Adverse effects are listed in decreasing order of severity. Hypersensitivity Anaphylaxis, rash, urticaria, subacute cutaneous lupus erythematosus-like reactions, photosensitivity. Cardiovascular Arrhythmia, postural hypotension.
Metabolic Diabetes mellitus, hyperkalemia, hypokalemia, hyponatremia, acidosis, hypercalcemia, hyperglycemia, glycosuria, hyperuricemia, hypochloremia. Gastrointestinal Jaundice and/or liver enzyme abnormalities, pancreatitis, nausea and vomiting, diarrhea, constipation, abdominal pain. Renal Acute renal failure (one case of irreversible renal failure has been reported), interstitial nephritis, renal stones composed primarily of triamterene, elevated BUN and serum creatinine, abnormal urinary sediment.
Hematologic Leukopenia, thrombocytopenia and purpura, megaloblastic anemia. Musculoskeletal Muscle cramps. Central Nervous System Weakness, fatigue, dizziness, headache, dry mouth.
Miscellaneous Impotence, sialadenitis. Thiazides alone have been shown to cause the following additional adverse reactions: Central Nervous System Paresthesias, vertigo. Ophthalmic Xanthopsia, transient blurred vision.
Respiratory Allergic pneumonitis, pulmonary edema, respiratory distress. Other Necrotizing vasculitis, exacerbation of lupus. Hematologic Aplastic anemia, agranulocytosis, hemolytic anemia.
Neonate and Infancy Thrombocytopenia and pancreatitis – rarely, in newborns whose mothers have received thiazides during pregnancy. Skin Erythema multiforme, including Stevens-Johnson syndrome; exfoliative dermatitis, including toxic epidermal necrolysis. Postmarketing Experience Non-Melanoma Skin Cancer Hydrochlorothiazide is associated with an increased risk of non-melanoma skin cancer.
In a study conducted in the Sentinel System, increased risk was predominantly for squamous cell carcinoma (SCC) and in white patients taking large cumulative doses. The increased risk for SCC in the overall population was approximately 1 additional case per 16,000 patients per year, and for white patients taking a cumulative dose of ≥50,000 mg the risk increase was approximately 1 additional SCC case for every 6,700 patients per year. To report SUSPECTED ADVERSE REACTIONS, contact Sandoz Inc. at 1-800-525-8747 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
🔄 Drug Interactions ▾
Drug Interactions Angiotensin-Converting Enzyme Inhibitors Potassium-sparing agents should be used with caution in conjunction with angiotensin-converting enzyme (ACE) inhibitors due to an increased risk of hyperkalemia. Oral Hypoglycemic Drugs Concurrent use with chlorpropamide may increase the risk of severe hyponatremia. Nonsteroidal Anti-Inflammatory Drugs A possible interaction resulting in acute renal failure has been reported in a few patients on triamterene and hydrochlorothiazide when treated with indomethacin, a nonsteroidal anti-inflammatory agent.
Caution is advised in administering nonsteroidal anti-inflammatory agents with triamterene and hydrochlorothiazide. Lithium Lithium generally should not be given with diuretics because they reduce its renal clearance and increase the risk of lithium toxicity. Read prescribing information for lithium preparations before use of such concomitant therapy with triamterene and hydrochlorothiazide.
Surgical Considerations Thiazides have been shown to decrease arterial responsiveness to norepinephrine (an effect attributed to loss of sodium). This diminution is not sufficient to preclude effectiveness of the pressor agent for therapeutic use. Thiazides have also been shown to increase the paralyzing effect of nondepolarizing muscle relaxants such as tubocurarine (an effect attributed to potassium loss); consequently, caution should be observed in patients undergoing surgery.
Other Considerations Concurrent use of hydrochlorothiazide with amphotericin B or corticosteroids or corticotropin (ACTH) may intensify electrolyte imbalance, particularly hypokalemia, although the presence of triamterene minimizes the hypokalemic effect. Thiazides may add to or potentiate the action of other antihypertensive drugs. See INDICATIONS AND USAGE for concomitant use with other antihypertensive drugs.
The effect of oral anticoagulants may be decreased when used concurrently with hydrochlorothiazide; dosage adjustments may be necessary. Triamterene and hydrochlorothiazide may raise the level of blood uric acid; dosage adjustments of antigout medication may be necessary to control hyperuricemia and gout. The following agents given together with triamterene may promote serum potassium accumulation and possibly result in hyperkalemia because of the potassium-sparing nature of triamterene, especially in patients with renal insufficiency: blood from blood bank (may contain potassium up to 30 mEq/L of plasma or up to 65 mEq/L of whole blood when stored for more than 10 days); low-salt milk (may contain potassium up to 60 mEq/L); potassium-containing medications (such as parenteral penicillin G potassium); salt substitutes (most contain substantial amounts of potassium).
Exchange resins, such as sodium polystyrene sulfonate, whether administered orally or rectally, reduce serum potassium levels by sodium replacement of the potassium; fluid retention may occur in some patients because of the increased sodium intake. Chronic or overuse of laxatives may reduce serum potassium levels by promoting excessive potassium loss from the intestinal tract; laxatives may interfere with the potassium-retaining effects of triamterene. The effectiveness of methenamine may be decreased when used concurrently with hydrochlorothiazide because of alkalinization of the urine.
Information for Patients Non-Melanoma Skin Cancer Instruct patients taking hydrochlorothiazide to protect skin from the sun and undergo regular skin cancer screening.
🔄 Drug / Laboratory Test Interactions ▾
Drug/Laboratory Test Interactions Triamterene and quinidine have similar fluorescence spectra; thus, triamterene and hydrochlorothiazide will interfere with the fluorescent measurement of quinidine.
🤰 Pregnancy ▾
Pregnancy Teratogenic Effects Triamterene and Hydrochlorothiazide Animal reproduction studies to determine the potential for fetal harm by triamterene and hydrochlorothiazide have not been conducted. However, a One Generation Study in the rat approximated composition of triamterene and hydrochlorothiazide by using a 1:1 ratio of triamterene to hydrochlorothiazide (30:30 mg/kg/day); there was no evidence of teratogenicity at those doses which were, on a body-weight basis, 15 and 30 times, respectively, the MRHD, and on the basis of body surface area, 3.1 and 6.2 times, respectively, the MRHD.
The safe use of triamterene and hydrochlorothiazide in pregnancy has not been established since there are no adequate and well-controlled studies with triamterene and hydrochlorothiazide in pregnant women. Triamterene and hydrochlorothiazide should be used during pregnancy only if the potential benefit justifies the risk to the fetus. Triamterene Reproduction studies have been performed in rats at doses as high as 20 times the MRHD on the basis of body weight and 6 times the human dose on the basis of body surface area without evidence of harm to the fetus due to triamterene.
Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed. Hydrochlorothiazide Hydrochlorothiazide was orally administered to pregnant mice and rats during respective periods of major organogenesis at doses up to 3,000 and 1,000 mg/kg/day, respectively. At these doses, which are multiples of the MRHD equal to 3,000 for mice and 1,000 for rats, based on body weight, and equal to 282 for mice and 206 for rats, based on body surface area, there was no evidence of harm to the fetus.
There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed. Nonteratogenic Effects Thiazides and triamterene have been shown to cross the placental barrier and appear in cord blood.
The use of thiazides and triamterene in pregnant women requires that the anticipated benefit be weighed against possible hazards to the fetus. These hazards include fetal or neonatal jaundice, pancreatitis, thrombocytopenia, and possible other adverse reactions which have occurred in the adult.
🧒 Pediatric Use ▾
Pediatric Use Safety and effectiveness in pediatric patients have not been established.
🆘 Overdosage ▾
OVERDOSAGE Electrolyte imbalance is the major concern (see WARNINGS ). Symptoms reported include: polyuria, nausea, vomiting, weakness, lassitude, fever, flushed face, and hyperactive deep tendon reflexes. If hypotension occurs, it may be treated with pressor agents such as levarterenol to maintain blood pressure.
Carefully evaluate the electrolyte pattern and fluid balance. Induce immediate evacuation of the stomach through emesis or gastric lavage. There is no specific antidote.
Reversible acute renal failure following ingestion of 50 tablets of a product containing a combination of 50 mg triamterene and 25 mg hydrochlorothiazide has been reported. Although triamterene is largely protein-bound (approximately 67%), there may be some benefit to dialysis in cases of overdosage.
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Triamterene and hydrochlorothiazide is a diuretic/antihypertensive drug product that combines natriuretic and antikaliuretic effects. Each component complements the action of the other. The hydrochlorothiazide component blocks the reabsorption of sodium and chloride ions, and thereby increases the quantity of sodium traversing the distal tubule and the volume of water excreted.
A portion of the additional sodium presented to the distal tubule is exchanged there for potassium and hydrogen ions. With continued use of hydrochlorothiazide and depletion of sodium, compensatory mechanisms tend to increase this exchange and may produce excessive loss of potassium, hydrogen, and chloride ions. Hydrochlorothiazide also decreases the excretion of calcium and uric acid, may increase the excretion of iodide, and may reduce glomerular filtration rate.
The exact mechanism of the antihypertensive effect of hydrochlorothiazide is not known. The triamterene component of triamterene and hydrochlorothiazide capsule exerts its diuretic effect on the distal renal tubule to inhibit the reabsorption of sodium in exchange for potassium and hydrogen ions. Its natriuretic activity is limited by the amount of sodium reaching its site of action.
Although it blocks the increase in this exchange that is stimulated by mineralocorticoids (chiefly aldosterone), it is not a competitive antagonist of aldosterone and its activity can be demonstrated in adrenalectomized rats and patients with Addison’s disease. As a result, the dose of triamterene required is not proportionally related to the level of mineralocorticoid activity but is dictated by the response of the individual patients and the kaliuretic effect of concomitantly administered drugs. By inhibiting the distal tubular exchange mechanism, triamterene maintains or increases the sodium excretion and reduces the excess loss of potassium, hydrogen, and chloride ions induced by hydrochlorothiazide.
As with hydrochlorothiazide, triamterene may reduce glomerular filtration and renal plasma flow. Via this mechanism, it may reduce uric acid excretion although it has no tubular effect on uric acid reabsorption or secretion. Triamterene does not affect calcium excretion.
No predictable antihypertensive effect has been demonstrated for triamterene. Duration of diuretic activity and effective dosage range of the hydrochlorothiazide and triamterene components are similar. Onset of diuresis with triamterene and hydrochlorothiazide takes place within one hour, peaks at two to three hours, and tapers off during the subsequent seven to nine hours.
Triamterene and hydrochlorothiazide capsules are well absorbed. Upon administration of a single oral dose to fasted normal male volunteers, mean pharmacokinetic parameters were determined ( Table 1 ). Table 1.
Mean Pharmacokinetic Parameters after Single Oral Dose in Fasted Male Volunteers AUC (0-48) , C max , T max , and Ae represent area under the plasma concentration versus time plot, maximum plasma concentration, time to reach C max , and amount excreted in urine over 48 hours. AUC (0-48) ng*h/mL (± SD) C max ng/mL (± SD) Median T max h Ae Mg (± SD) Triamterene 148.7 (87.9) 46.4 (29.4) 1.1 2.7 (1.4) Hydroxytriamterene sulfate 1,865 (471) 720 (364) 1.3 19.7 (6.1) Hydrochlorothiazide 834 (177) 135.1 (35.7) 2.0 14.3 (3.8) A capsule of triamterene and hydrochlorothiazide is bioequivalent to a single entity 25-mg hydrochlorothiazide tablet and 37.5-mg triamterene capsule used in the double-blind clinical trial below (see CLINICAL TRIALS ).
In a limited study involving 12 subjects, coadministration of triamterene and hydrochlorothiazide capsule with a high-fat meal resulted in: (1) an increase in the mean bioavailability of triamterene by about 67% (90% confidence interval = 0.99, 1.90), p-hydroxytriamterene sulfate by about 50% (90% confidence interval = 1.06, 1.77), hydrochlorothiazide by about 17% (90% confidence interval = 0.90, 1.34); (2) increases in…
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED Capsules containing 37.5 mg triamterene, USP and 25 mg hydrochlorothiazide, USP are available for oral administration as white capsules with single black ink bands imprinted GG 606 in black ink and supplied as: NDC 63629-8732-1 bottles of 100 Store at controlled room temperature 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature]. Protect from moisture. Protect from light.
Dispense in a tight, light-resistant container. KEEP OUT OF THE REACH OF CHILDREN. Repackaged/Relabeled by: Bryant Ranch Prepack, Inc.
Burbank, CA 91504
📋 Description ▾
DESCRIPTION Triamterene, USP is an antikaliuretic agent and hydrochlorothiazide, USP is a diuretic/antihypertensive agent. At 50°C, triamterene, USP is practically insoluble in water (less than 0.1%). It is soluble in formic acid, sparingly soluble in methoxyethanol, and very slightly soluble in alcohol.
Triamterene, USP is 2,4,7-triamino-6-phenylpteridine with a chemical formula of C 12 H 11 N 7 and a molecular weight of 253.27. The structural formula for triamterene is: TRIAMTERENE Hydrochlorothiazide, USP is slightly soluble in water. It is soluble in dilute ammonia, dilute aqueous sodium hydroxide, and dimethylformamide.
It is sparingly soluble in methanol. Hydrochlorothiazide, USP is 6-chloro-3,4-dihydro-2H-1,2, 4-benzothiadiazine-7-sulfonamide 1,1-dioxide with a chemical formula of C 7 H 8 ClN 3 O 4 S 2 and a molecular weight of 297.75. The structural formula for hydrochlorothiazide is: HYDROCHLOROTHIAZIDE Each capsule, for oral administration, contains 37.5 mg triamterene, USP and 25 mg hydrochlorothiazide, USP.
The 37.5 mg triamterene, USP and 25 mg hydrochlorothiazide, USP capsule inactive ingredients include: citric acid, corn starch, glycine, anhydrous lactose, magnesium stearate, Polysorbate 80, povidone, and sodium starch glycolate. The capsule shells and imprinting inks contain: D & C Yellow #10 Aluminum Lake, FD & C Blue #1 Aluminum Lake, FD & C Blue #2 Aluminum Lake, FD & C Red #40 Aluminum Lake, gelatin, pharmaceutical glaze, propylene glycol, synthetic black iron oxide, and titanium dioxide. The 37.5 mg triamterene, USP and 25 mg hydrochlorothiazide, USP capsules meets USP Dissolution Test 3 .