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Triamterene and Hydrochlorothiazide 25; 37.5 mg; mg Capsule, 100-count

by RPK Pharmaceuticals, Inc. · 100 CAPSULE in 1 BOTTLE (53002-1246-0)
NDC 53002-1246-00
🏷️ FDA NDC (as labeled) 53002-1246-0 billing pads the package segment with a zero
This package
Contains100-count Pack sizes2 compare ↓
Also comes in: 30 capsules 53002-1246-03
Rx only Generic Discontinued Non-controlled ⚠ Inactivated by FDA
🗂️ Data synced Jul 14, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →
⚠️
Excluded from the active FDA NDC Directory. FDA inactivated this product’s listing record, so it is excluded from the active NDC Directory. The listing was last certified through Dec 2024. A label may still appear on DailyMed, but the NDC is no longer in the current FDA NDC Directory. Search the FDA NDC Directory ↗

🆔 Identity & classification

FDA NDC (as labeled) 53002-1246-0
Product NDC 53002-1246
11-digit billing NDC 53002124600
Application # ANDA201407
SPL Set ID e71c754d-78bd-42f5-8691-5c4118ca859f
Chemical class Decreased Renal K+ Excretion [PE], Increased Diuresis [PE], Increased Diuresis [PE], Potassium-sparing Diuretic [EPC], Thiazide Diuretic [EPC], Thiazides
DEA schedule Non-controlled
Marketing category ANDA
Marketing status Discontinued
FDA listing status Inactivated by FDA (certified through Dec 2024)
Route ORAL
Dosage form CAPSULE
Substance HYDROCHLOROTHIAZIDE; TRIAMTERENE
TE code (Orange Book) AB · RLD · RS
Why two NDCs? The FDA registers this code as 53002-1246-0 — a 5-4-1 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the package segment → 53002-1246-00. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

🏭 Manufacturer & labeler

LabelerRPK Pharmaceuticals, Inc.
Application holderLANNETT CO INC
FDA applicationANDA201407 (ANDA)
Labeler code53002
Product typeHuman Prescription Drug
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

🩺 Clinical

📗 Our plain-language guide HelloPharmacist
  • 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?
📖 Read our full Triamterene and Hydrochlorothiazide guide →
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

🧪 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.

Loading inactive ingredients from the official FDA label in the background. No external source is being called by this page request.
Where does this data come from?
Source: official FDA Structured Product Labeling (SPL) via DailyMed and the openFDA label index. Structured IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

💲 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 systemPer eachPer 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.
ℹ️
No price is published for this exact package yet. CMS surveys NADAC per package size, so a different pack of the same drug often has one.
Try another pack size: 30 capsules
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

🔁 Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Triamterene and Hydrochlorothiazide 25; 37.5 mg/1; mgthis 53002-1246-00 RPK 100 capsules — AB Discontinued —
About this product: this is a generic version of the medicine. FDA equivalence ratings are shown when available, and other versions are listed above, least expensive first.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

⏳ Availability & generic status

📍
2026
Currently FDA-listed
listed with the FDA
🔓
·
Generic on the market
this product is a generic
✅This is a generic drug

This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.

Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

🔬 Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for Triamterene and Hydrochlorothiazide — the ingredient across all brands.

Top reported reactions

Nausea407
Fatigue399
Pain327
Dizziness318
Diarrhoea309
Headache290
Dyspnoea286

Age at onset

Neonate1
Infant1
Adult323
Elderly337

Reporter sex

6,113 reports
Male · 27%
Female · 73%
Unknown · 0%

Serious outcomes

Hospitalization1,569
Life-threatening160
Reports over time (by year) — tap or hover for the count & year
2021 2022 2024 2026 187 0
Most recent year is provisional (FAERS lags ~3 months).
Where does this data come from?
Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

📦 Packaging — all sizes for this product

Package NDCDescription Marketing startStatus
53002-1246-00 You're viewing this 100 CAPSULE in 1 BOTTLE (53002-1246-0) 2018-10-01 Inactivated by FDA
53002-1246-03 30 CAPSULE in 1 BOTTLE (53002-1246-3) 2018-10-01 Inactivated by FDA

You're viewing the largest of 2 pack sizes for this product.

Pack size FAQ

What quantity is in NDC 53002-1246-00?
NDC 53002-1246-00 is a 100-count package — 100 capsule in 1 bottle.
What is the difference between NDC 53002-1246-00 and NDC 53002-1246-03?
Both are Triamterene and Hydrochlorothiazide 25; 37.5 mg; mg Capsule — the drug itself is identical. NDC 53002-1246-00 is the 100-count package, while NDC 53002-1246-03 is the 30 capsules package.
What NDC number is used to bill for this package of Triamterene and Hydrochlorothiazide 25; 37.5 mg; mg Capsule?
Bill NDC 53002-1246-00 — the 11-digit billing format is 53002124600. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

🧭 About this NDC listing & data coverage

Finished prescription product No longer marketed (per FDA listing data)
What data is (and isn’t) available for this NDC — tap to expand
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 — Not published for this NDC No photo available yet for this listing.
Inactive ingredients (structured) — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is 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.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
What does the discontinued status mean for this NDC?
The labeler reported a marketing end date (or the listing was delisted), so this specific package is no longer actively marketed. Remaining stock may still be dispensed for a time, and the NDC stays valid for historical records and claims — but data feeds (pricing, labeling) typically stop updating for it. Other package sizes or other manufacturers' versions of the same medication may still be marketed — see the equivalents section where available.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The FDA registers it as 53002-1246-0, which is what is printed on the packaging and shown on DailyMed. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero: 53002-1246-00, written without dashes as 53002124600. The Identity section at the top of this page lists every form of this code.
What do the three segments of this NDC mean?
In 53002-1246-00, the first segment (53002) is the labeler code FDA assigned to RPK Pharmaceuticals, Inc.; the middle segment (1246) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (00) identifies this exact package size and type. Together they name one specific package of one specific product.
Does this product come in other package sizes?
Yes — the FDA directory lists 1 other package presentation of this same product, including 30 capsules (53002-1246-03). Each has its own NDC and its own page — see the package list near the top of this page.
Who lists this product with the FDA?
RPK Pharmaceuticals, Inc. is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.

📄 Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🚨 Boxed Warning 91 words ▾

Hyperkalemia: Abnormal elevation of serum potassium levels (greater than or equal to 5.5 mEq/liter) can occur with all potassium-sparing diuretic combinations, including triamterene and hydrochlorothiazide capsules, USP. 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 capsules, USP, when dosages are changed, or with any illness that may influence renal function.

🎯 Indications and Usage ~1 min read ▾

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 capsules, USP are indicated for the treatment of hypertension or edema in patients who develop hypokalemia on hydrochlorothiazide alone. Triamterene and hydrochlorothiazide capsules, USP are also indicated for those patients who require a thiazide diuretic and in whom the development of hypokalemia cannot be risked.

Triamterene and hydrochlorothiazide capsules, USP may be used alone or as an adjunct to other antihypertensive drugs, such as beta-blockers. Since triamterene and hydrochlorothiazide capsules, USP 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 35 words ▾

DOSAGE AND ADMINISTRATION The usual dose of triamterene and hydrochlorothiazide capsules, USP is 1 or 2 capsules given once daily, with appropriate monitoring of serum potassium and of the clinical effect (see WARNINGS, Hyperkalemia ).

⛔ Contraindications 140 words ▾

CONTRAINDICATIONS Antikaliuretic Therapy and Potassium Supplementation: Triamterene and hydrochlorothiazide capsules, USP 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 capsules, USP 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 capsules, USP are 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 capsules, USP should not be used in patients with pre-existing elevated serum potassium.

⚠️ Warnings ~2 min read ▾

WARNINGS Hyperkalemia: Abnormal elevation of serum potassium levels (greater than or equal to 5.5 mEq/liter) can occur with all potassium-sparing diuretic combinations, including triamterene and hydrochlorothiazide capsules, USP. 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 capsules, USP, 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 capsules, USP 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 capsules, USP 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 capsules, USP are 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 capsules, USP are 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 ~1 min read ▾

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.

🔄 Drug Interactions ~2 min read ▾

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 capsules, USP when treated with indomethacin, a nonsteroidal anti-inflammatory agent.

Caution is advised in administering nonsteroidal anti-inflammatory agents with triamterene and hydrochlorothiazide capsules, USP. 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 capsules, USP.

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 capsules, USP 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.

🤰 Pregnancy ~2 min read ▾

Pregnancy: Teratogenic Effects : Triamterene and hydrochlorothiazide capsules, USP: Animal reproduction studies to determine the potential for fetal harm by triamterene and hydrochlorothiazide capsules, USP have not been conducted. However, a One Generation Study in the rat approximated composition of triamterene and hydrochlorothiazide capsules, USP 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 capsules, USP in pregnancy has not been established since there are no adequate and well-controlled studies with triamterene and hydrochlorothiazide capsules, USP in pregnant women. Triamterene and hydrochlorothiazide capsules, USP 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 12 words ▾

Pediatric Use: Safety and effectiveness in pediatric patients have not been established.

🆘 Overdosage 111 words ▾

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 ~3 min read ▾

CLINICAL PHARMACOLOGY The triamterene and hydrochlorothiazide capsule 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 capsules, USP 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 of triamterene and hydrochlorothiazide capsules, USP are similar. Onset of diuresis with triamterene and hydrochlorothiazide capsules, USP takes place within 1 hour, peaks at 2 to 3 hours, and tapers off during the subsequent 7 to 9 hours.

Triamterene and hydrochlorothiazide capsules, USP 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 a 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 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.

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 capsules, USP 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), hydroch…

📦 How Supplied / Storage and Handling 18 words ▾

HOW SUPPLIED Product: 53002-1246 NDC: 53002-1246-3 30 CAPSULE in a BOTTLE NDC: 53002-1246-0 100 CAPSULE in a BOTTLE

📋 Description 219 words ▾

DESCRIPTION Each triamterene and hydrochlorothiazide capsule for oral use contains triamterene 37.5 mg and hydrochlorothiazide 25 mg. Hydrochlorothiazide is a diuretic/antihypertensive agent and triamterene is an antikaliuretic agent. Hydrochlorothiazide is slightly soluble in water.

It is soluble in dilute ammonia, dilute aqueous sodium hydroxide, and dimethylformamide. It is sparingly soluble in methanol. Hydrochlorothiazide is 6-chloro-3,4-dihydro-2 H -1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide, and its structural formula is: Molecular Formula: C 7 H 8 CIN 3 O 4 S 2 M.W.

297.74 At 50°C, triamterene 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 is 2,4,7-triamino-6-phenylpteridine and its structural formula is: Molecular Formula: C 12 H 11 N 7 M.W.

253.26 Inactive ingredients consist of lactose monohydrate, pregelatinized starch, sodium starch glycolate, polysorbate 80, citric acid anhydrous, povidone, and magnesium stearate. The capsule shell consists of titanium dioxide and gelatin. The capsule imprinting ink consists of shellac glaze in ethanol, iron oxide black, n-butyl alcohol, propylene glycol, ethanol, methanol, FD&C Blue # 2 Aluminum Lake, FD&C Red # 40 Aluminum Lake, FD&C Blue # 1 Aluminum Lake, and D&C Yellow # 10 Aluminum Lake.

Triamterene and hydrochlorothiazide capsules, USP meet USP Dissolution Test 3 as published in the current USP monograph for Triamterene and Hydrochlorothiazide Capsules. hctz-molec-struc triamterene-molec-struc

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
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