HomeNDC LookupIngredientsAtenolol And Chlorthalidone › 00591-5782-01
Atenolol and Chlorthalidone 50 mg; 25 mg Tablet, 100-count — NDC 00591-5782-01 package photo

Atenolol and Chlorthalidone 50 mg; 25 mg Tablet, 100-count

by Actavis Pharma, Inc. · 100 TABLET in 1 BOTTLE (0591-5782-01)
NDC 00591-5782-01
🏷️ FDA NDC (as labeled) 0591-5782-01 billing pads the labeler segment with a zero
This package
Contains100-count Cost per ea$0.2331 NADAC Per package$23.31 / 100 tablets Pack sizes3 compare ↓
Also priced by: Medicaid pays $0.3887/unit · Part D plans $0.3852/unit — full pricing hub ↓
On market Non-controlled
🗂️ Data synced Sep 10, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

🆔 Identity & classification

FDA NDC (as labeled) 0591-5782-01
Product NDC 0591-5782
11-digit billing NDC 00591578201
NCPDP billing unit EA — each (per item)
SPL Set ID a6794dfa-adbb-491b-9d48-f89a44e866c5
DEA schedule Non-controlled
Marketing category DRUG FOR FURTHER PROCESSING
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 1992-08-01
Dosage form TABLET
Substance ATENOLOL; CHLORTHALIDONE
GCN Seq No 000420
GCN 66990
HICL code 000147
Ingredient (HICL) Atenolol/Chlorthalidone
HIC1 code J
Therapeutic class — broad (HIC1) Autonomic Nervous System
HIC2 code J7
Therapeutic class — intermediate (HIC2) Antiadrenergics
HIC3 code J7H
Therapeutic class — specific (HIC3) Beta-Blockers And Thiazide,Thiazide-Like Diuretics
AHFS code 12:16.08.08
AHFS class Selective Beta-Adrenergic Blocking Agent
FDB label name ATENOLOL-CHLORTHALIDONE 50-25
FDB brand name Atenolol-Chlorthalidone
Legend status F — Federal legend — prescription drug or device
Why two NDCs? The FDA registers this code as 0591-5782-01 — a 4-4-2 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 labeler segment → 00591-5782-01. 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

LabelerActavis Pharma, Inc.
Labeler code00591
First marketedAug 1992
Product typeDrug For Further Processing
Portfolio324 products on file
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

Label name ATENOLOL-CHLORTHALIDONE 50-25 Ingredient Atenolol/Chlorthalidone
📖 What it is MedlinePlus · NLM

Atenolol is used to treat high blood pressure, angina (chest pain) and improve survival after a heart attack. Atenolol is in a class of medications called beta blockers. It works by relaxing blood vessels and slowing heart rate to improve blood flow and decrease blood pressure.

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • This tablet combines two medicines — atenolol and chlorthalidone — to lower your blood pressure. Controlling high blood pressure is important because it significantly reduces your...
  • Please don't stop taking this medication suddenly without talking to your doctor first. Stopping abruptly — especially if you have any underlying heart disease — can cause a reboun...
  • Can I just stop taking it if I feel fine or if I'm having side effects?
  • Yes, and this is really important. Atenolol can mask one of the main warning signs of low blood sugar — a racing heart. So if your blood sugar drops, you might not feel the usual r...
📖 Read our full Atenolol / Chlorthalidone 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.

💊 What it looks like

Color white
ShapeRound
ImprintDAN;5783
Size1 mm
ScoringNot scored
One label can cover several strengths, so colors may be combined — always confirm a loose pill against the dispensed prescription label or a pharmacist.
Where does this data come from?
Physical description (imprint, shape, color, scoring, coating) from this product’s FDA Structured Product Labeling (SPL), mirrored from DailyMed / openFDA.

🧪 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.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

  • UNII OP1R32D61U
    Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
  • 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.
  • 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.
  • 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.

4 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?
Data sourced from official FDA Structured Product Labeling (SPL) via DailyMedingredient 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

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 eaPer package
Retail pharmacies payNADAC · weekly $0.233 $23.31 / 100 tablets
Medicaid paysCMS SDUD · 12 mo $0.3887 $38.87 / 100 tablets
Medicare drug plans payPart D · Q2 2026 $0.3852 $38.52 / 100 tablets
NADAC price history (per ea) — tap or hover for the price & month
Dec 2021 Jul 2022 Dec 2025 Aug 2026 $0.386 $0.233
▼ Down 33% over the last 24 months.
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
Atenolol and Chlorthalidone 50 mg/1; 25 mgthis 00591-5782-01 Actavis 100 tablets $0.233 Availability likely
Atenolol and Chlorthalidone 50 mg/1; 25 mg 16714-0936-01 Northstar 100 tablets $0.233 AB Availability likely
Atenolol and Chlorthalidone 50 mg/1; 25 mg 29300-0400-01 Unichem 100 tablets $0.233 AB Availability likely
Atenolol and Chlorthalidone 50 mg/1; 25 mg 70710-1167-01 Zydus 100 tablets $0.233 AB Availability likely
Atenolol and Chlorthalidone 50 mg/1; 25 mg 70954-0390-10 ANI 100 tablets $0.233 AB Availability likely
Atenolol And Chlorthalidone 25 mg/1; 50 mg 10135-0733-01 MARLEX 100 tablets AB FDA listed
Tenoretic 50 mg/1; 25 mg 24979-0256-07 Upsher-Smith 90 tablets Discontinued
Atenolol and Chlorthalidone 50 mg/1; 25 mg 55289-0993-30 PD-Rx 30 tablets AB FDA listed
Atenolol and Chlorthalidone 50 mg/1; 25 mg 70771-1372-01 Zydus 100 tablets AB FDA listed
About this product: other versions of the same ingredient, strength and form are listed above, least expensive first, with FDA equivalence ratings where available.
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

🏛️
1992
On the market since
Aug 1992
📍
2026
Currently FDA-listed
34 years listed
🔓
·
Generic versions listed
see equivalents
Generic appears available

FDA-approved generic versions are listed, and recent pricing/market data suggests they may be available — see Therapeutic equivalents.

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.

🗺️ Medicaid utilization & spend

📍 This exact package only: Medicaid data is reported per full 11-digit NDC — labeler, product and pack size — so every number here is for 00591-5782-01, not the drug overall. Other pack sizes report separately.
💊 Pharmacy benefit only: These are Medicaid outpatient pharmacy claims, billed by NDC. They exclude the medical benefit — clinic- or hospital-administered drugs billed under HCPCS J-codes — so drugs used mostly that way (e.g. Avastin, Lucentis, Keytruda) can look low or missing here. That’s expected, not an error.
📅 Q1 2025 – Q4 2025 · 4 quarters of data
ⓘ The newest quarter is usually incomplete when first published; states restate recent quarters in later CMS releases, so the latest figures typically revise upward. State coverage-policy changes can also shift quarter-to-quarter totals.
Prescriptions last 4 qtrs
4.1K
Units reimbursed last 4 qtrs
210.1K
Gross reimbursed last 4 qtrs
$81.7K
Avg / prescription
$20.14
Avg / unit
$0.3887
Latest quarter Q4 2025
879Rx
Medicaid pays / ea
$0.3887
gross reimbursed
vs
NADAC / ea
$0.2331
acquisition cost
=
Spread
+$0.1556
+67% vs cost
What Medicaid paid per ea (before rebates; includes the pharmacy’s dispensing fee) compared with NADAC — the average price pharmacies pay to buy the drug. A positive spread means Medicaid reimbursed more than the purchase price, before manufacturer rebates.
Fee-for-service vs managed care
33% FFS 67% MCO
Fee-for-service · 1,334 Rx Managed care · 2,722 Rx
State Medicaid map
Alaska: no data reported AK Maine: no data reported ME Washington: no data reported WA Idaho: no data reported ID Montana: no data reported MT North Dakota: no data reported ND Minnesota: no data reported MN Wisconsin: no data reported WI Michigan: 808 units · 8.1 per 100k residents MI New York: 29,344 units · 150 per 100k residents NY Vermont: no data reported VT New Hampshire: no data reported NH Oregon: no data reported OR Nevada: 5,185 units · 162 per 100k residents NV Wyoming: no data reported WY South Dakota: no data reported SD Iowa: no data reported IA Illinois: 2,322 units · 18.5 per 100k residents IL Indiana: no data reported IN Ohio: no data reported OH Pennsylvania: 690 units · 5.3 per 100k residents PA New Jersey: 3,927 units · 42.3 per 100k residents NJ Massachusetts: 17,880 units · 255 per 100k residents MA California: 24,318 units · 62.4 per 100k residents CA Utah: no data reported UT Colorado: no data reported CO Nebraska: no data reported NE Missouri: no data reported MO Kentucky: 1,440 units · 31.8 per 100k residents KY West Virginia: no data reported WV Virginia: 17,377 units · 199 per 100k residents VA Maryland: 16,239 units · 263 per 100k residents MD Connecticut: 11,500 units · 318 per 100k residents CT Rhode Island: 3,120 units · 285 per 100k residents RI Arizona: 2,640 units · 35.5 per 100k residents AZ New Mexico: no data reported NM Kansas: no data reported KS Arkansas: no data reported AR Tennessee: 1,665 units · 23.4 per 100k residents TN North Carolina: 14,084 units · 130 per 100k residents NC South Carolina: 5,884 units · 110 per 100k residents SC Delaware: no data reported DE Oklahoma: no data reported OK Louisiana: 5,670 units · 124 per 100k residents LA Mississippi: 1,830 units · 62.2 per 100k residents MS Alabama: 1,260 units · 24.7 per 100k residents AL Georgia: 6,525 units · 59.2 per 100k residents GA D.C.: 1,027 units · 151 per 100k residents DC Hawaii: no data reported HI Texas: 6,990 units · 22.9 per 100k residents TX Florida: 26,125 units · 116 per 100k residents FL
Units reimbursed · per 100k residents
5.3318
gray = no data reported
Colors are per 100,000 residents, so big states don’t automatically dominate. Tap or hover a state for its actual totals.
Tap or hover a state
…for its Medicaid breakdown
🏆 Top states by units · per 100k residents
1 Connecticut 318 /100k
2 Rhode Island 285 /100k
3 Maryland 263 /100k
4 Massachusetts 255 /100k
5 Virginia 199 /100k
6 Nevada 162 /100k
7 D.C. 151 /100k
8 New York 150 /100k
National units — by quarter
💵 About the dollar figures: “reimbursed” is what Medicaid paid pharmacies before confidential manufacturer rebates, so the program’s real net cost is lower than these numbers. Fee-for-service and managed-care claims are combined unless split above. Source: CMS State Drug Utilization Data; per-100k rates use 2023 Census population estimates.

💊 Medicaid utilization by pack size

Medicaid (SDUD) totals over the four most recent reported quarters for every package size of this drug — handy when a specific package (e.g. a starter/titration pack) carries little or no Medicaid volume on its own.
68970 tablets00591-5782-00 No Medicaid data
82764 tablets00591-5782-77 No Medicaid data
Drug total (last 4 qtrs): 4,056 Rx · 210,105 units · $81,674 gross reimbursed
Tap a pack size to open its page. Source: CMS State Drug Utilization Data, last 4 quarters.

📦 Packaging — all sizes for this product

Package NDCDescription Per unit Per pack Marketing startStatus
00591-5782-01 You're viewing this 100 TABLET in 1 BOTTLE (0591-5782-01) $0.2331 / ea $23.31 1992-08-01 Active
00591-5782-00 68970 TABLET in 1 BOX (0591-5782-00) Active
00591-5782-77 82764 TABLET in 1 CONTAINER (0591-5782-77) Active

You're viewing the smallest of 3 pack sizes for this product.

In Medicaid, this is the most-dispensed pack of this product — about 100% of fills over the last four reported quarters. See all packs ↓

Pack size FAQ

What quantity is in NDC 00591-5782-01?
NDC 00591-5782-01 is a 100-count package — 100 tablet in 1 bottle.
What is the difference between NDC 00591-5782-01 and NDC 00591-5782-00?
Both are Atenolol and Chlorthalidone 50 mg; 25 mg Tablet — the drug itself is identical. NDC 00591-5782-01 is the 100-count package, while NDC 00591-5782-00 is the 68970 tablets package.
What NDC number is used to bill for this package of Atenolol and Chlorthalidone 50 mg; 25 mg Tablet?
Bill NDC 00591-5782-01 — the 11-digit billing format is 00591578201. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

Prices are the latest CMS NADAC pharmacy acquisition cost per NDC; per-pack figures are per-unit × pack quantity, shown only when the pack is denominated in the same measure NADAC prices.

🧭 About this NDC listing & data coverage

Listed for further processing / repackaging

What "drug for further processing" means

FDA lists this package under the "drug for further processing" marketing category: Actavis Pharma, Inc. supplies it to other companies for further processing or repackaging (blister cards that are later repackaged or co-packaged are a common example). The units themselves are a finished dosage form — which is why pricing or Medicaid data can still appear — but this exact package code may not be the presentation a retail pharmacy dispenses.

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 ✓ Available
Inactive ingredients (structured) ✓ Available
NADAC pharmacy acquisition price (CMS) ✓ Available
Orange Book / therapeutic-equivalence data — Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope.
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) ✓ Available
“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

Is this NDC FDA-approved?
An NDC listing does not by itself establish FDA approval — the NDC Directory records that a product is listed with FDA, not that it was reviewed and approved. This listing's marketing category is "Drug For Further Processing". Products approved under an application carry an NDA, ANDA, or BLA number.
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 0591-5782-01, 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: 00591-5782-01, written without dashes as 00591578201. 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 00591-5782-01, the first segment (00591) is the labeler code FDA assigned to Actavis Pharma, Inc.; the middle segment (5782) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (01) identifies this exact package size and type. Together they name one specific package of one specific product.
Is this package still being marketed?
Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by Actavis Pharma, Inc.. Listing status can change — the directory data on this page refreshes weekly.
Does this product come in other package sizes?
Yes — the FDA directory lists 2 other package presentations of this same product, including 68970 tablets (00591-5782-00), 82764 tablets (00591-5782-77). 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?
Actavis Pharma, 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.
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 FDA label FDA SPL

The complete FDA label for this product, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage ~2 min read

INDICATIONS AND USAGE Atenolol and chlorthalidone is indicated for the treatment of hypertension, to lower blood pressure. Lowering blood pressure lowers the risk of fatal and non-fatal cardiovascular events, primarily strokes and myocardial infarctions. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes including atenolol and chlorthalidone.

Control of high blood pressure should be part of comprehensive cardiovascular risk management, including, as appropriate, lipid control, diabetes management, antithrombotic therapy, smoking cessation, exercise, and limited sodium intake. Many patients will require more than 1 drug to achieve blood pressure goals. For specific advice on goals and management, see published guidelines, such as those of the National High Blood Pressure Education Program’s Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC).

Numerous antihypertensive drugs, from a variety of pharmacologic classes and with different mechanisms of action, have been shown in randomized controlled trials to reduce cardiovascular morbidity and mortality, and it can be concluded that it is blood pressure reduction, and not some other pharmacologic property of the drugs, that is largely responsible for those benefits. The largest and most consistent cardiovascular outcome benefit has been a reduction in the risk of stroke, but reductions in myocardial infarction and cardiovascular mortality also have been seen regularly.

Elevated systolic or diastolic pressure causes increased cardiovascular risk, and the absolute risk increase per mmHg is greater at higher blood pressures, so that even modest reductions of severe hypertension can provide substantial benefit. Relative risk reduction from blood pressure reduction is similar across populations with varying absolute risk, so the absolute benefit is greater in patients who are at higher risk independent of their hypertension (for example, patients with diabetes or hyperlipidemia), and such patients would be expected to benefit from more aggressive treatment to a lower blood pressure goal.

Some antihypertensive drugs have smaller blood pressure effects (as monotherapy) in black patients, and many antihypertensive drugs have additional approved indications and effects (e.g., on angina, heart failure, or diabetic kidney disease). These considerations may guide selection of therapy. This fixed dose combination drug is not indicated for initial therapy of hypertension.

If the fixed dose combination represents the dose appropriate to the individual patient's needs, it may be more convenient than the separate components.

⏱️ Dosage and Administration 186 words

DOSAGE AND ADMINISTRATION DOSAGE MUST BE INDIVIDUALIZED. (See INDICATIONS AND USAGE . ) Chlorthalidone is usually given at a dose of 25 mg daily; the usual initial dose of atenolol is 50 mg daily. Therefore, the initial dose should be one atenolol and chlorthalidone 50 mg/25 mg tablet given once a day.

If an optimal response is not achieved, the dosage should be increased to one atenolol and chlorthalidone 100 mg/25 mg tablet given once a day. When necessary, another antihypertensive agent may be added gradually beginning with 50 percent of the usual recommended starting dose to avoid an excessive fall in blood pressure. Since atenolol is excreted via the kidneys, dosage should be adjusted in cases of severe impairment of renal function.

No significant accumulation of atenolol occurs until creatinine clearance falls below 35 mL/min/1.73 m 2 (normal range is 100 mL/min/1.73 m 2 to 150 mL/min/1.73 m 2 ); therefore, the following maximum dosages are recommended for patients with renal impairment. Creatinine Clearance Atenolol Elimination (mL/min/1.73m 2 ) Half-Life (hrs) Maximum Dosage 15-35 16-27 50 mg daily <15 >27 50 mg every other day

Contraindications 35 words

CONTRAINDICATIONS Atenolol and chlorthalidone tablets are contraindicated in patients with: sinus bradycardia; heart block greater than first degree; cardiogenic shock; overt cardiac failure (see WARNINGS ); anuria; hypersensitivity to this product or to sulfonamide-derived drugs.

⚠️ Warnings ~3 min read

WARNINGS Cardiac Failure Sympathetic stimulation is necessary in supporting circulatory function in congestive heart failure, and beta blockade carries the potential hazard of further depressing myocardial contractility and precipitating more severe failure. IN PATIENTS WITHOUT A HISTORY OF CARDIAC FAILURE, continued depression of the myocardium with beta-blocking agents over a period of time can, in some cases, lead to cardiac failure. At the first sign or symptom of impending cardiac failure, patients should be treated appropriately according to currently recommended guidelines, and the response observed closely.

If cardiac failure continues despite adequate treatment, atenolol and chlorthalidone should be withdrawn. (See DOSAGE AND ADMINISTRATION . ) Renal and Hepatic Disease and Electrolyte Disturbances Since atenolol is excreted via the kidneys, atenolol and chlorthalidone should be used with caution in patients with impaired renal function. In patients with renal disease, thiazides may precipitate azotemia.

Since cumulative effects may develop in the presence of impaired renal function, if progressive renal impairment becomes evident, atenolol and chlorthalidone should be discontinued. In patients with impaired hepatic function or progressive liver disease, minor alterations in fluid and electrolyte balance may precipitate hepatic coma. Atenolol and chlorthalidone should be used with caution in these patients.

Ischemic Heart Disease Following abrupt cessation of therapy with certain beta-blocking agents in patients with coronary artery disease, exacerbations of angina pectoris and, in some cases, myocardial infarction have been reported. Therefore, such patients should be cautioned against interruption of therapy without the physician’s advice. Even in the absence of overt angina pectoris, when discontinuation of atenolol and chlorthalidone is planned, the patient should be carefully observed and should be advised to limit physical activity to a minimum.

Atenolol and chlorthalidone should be reinstated if withdrawal symptoms occur. Because coronary artery disease is common and may be unrecognized, it may be prudent not to discontinue atenolol and chlorthalidone therapy abruptly even in patients treated only for hypertension. Concomitant Use of Calcium Channel Blockers Bradycardia and heart block can occur and the left ventricular end diastolic pressure can rise when beta-blockers are administered with verapamil or diltiazem.

Patients with pre-existing conduction abnormalities or left ventricular dysfunction are particularly susceptible. (See PRECAUTIONS . ) Bronchospastic Diseases PATIENTS WITH BRONCHOSPASTIC DISEASE SHOULD, IN GENERAL, NOT RECEIVE BETA-BLOCKERS. Because of its relative beta 1 -selectivity, however, atenolol and chlorthalidone may be used with caution in patients with bronchospastic disease who do not respond to or cannot tolerate, other antihypertensive treatment.

Since beta 1 -selectivity is not absolute, the lowest possible dose of atenolol and chlorthalidone should be used and a beta 2 -stimulating agent (bronchodilator) should be made available. If dosage must be increased, dividing the dose should be considered in order to achieve lower peak blood levels. Major Surgery Chronically administered beta-blocking therapy should not be routinely withdrawn prior to major surgery, however the impaired ability of the heart to respond to reflex adrenergic stimuli may augment the risks of general anesthesia and surgical procedures.

Metabolic and Endocrine Effects Beta-blockers may prevent early warning signs of hypoglycemia, such as tachycardia, and increase the risk for severe or prolonged hypoglycemia at any time during treatment, especially in patients with diabetes mellitus or children and patients who are fasting (i.e., surgery, not eating regularly, or are vomiting). If severe hypoglycemia occurs, patients should be instructed to seek emergency treatment. Insulin requirements in diabetic patients may be…

🤒 Adverse Reactions ~2 min read

ADVERSE REACTIONS Atenolol and chlorthalidone tablets are usually well tolerated in properly selected patients. Most adverse effects have been mild and transient. The adverse effects observed for atenolol and chlorthalidone are essentially the same as those seen with the individual components.

Atenolol The frequency estimates in the following table were derived from controlled studies in which adverse reactions were either volunteered by the patient (US studies) or elicited, e.g., by checklist (foreign studies). The reported frequency of elicited adverse effects was higher for both atenolol and placebo-treated patients than when these reactions were volunteered. Where frequency of adverse effects for atenolol and placebo is similar, causal relationship to atenolol is uncertain.

Volunteered Total–Volunteered and Elicited (US Studies) (Foreign + US Studies) Atenolol Placebo Atenolol Placebo (n = 164) (n = 206) (n = 399) (n = 407) % % % % CARDIOVASCULAR Bradycardia 3 0 3 0 Cold Extremities 0 0.5 12 5 Postural Hypotension 2 1 4 5 Leg Pain 0 0.5 3 1 CENTRAL NERVOUS SYSTEM/ NEUROMUSCULAR Dizziness 4 1 13 6 Vertigo 2 0.5 2

0.2 Light-Headedness 1 0 3

0.7Tiredness 0.6 0.5 26 13 Fatigue 3 1 6 5 Lethargy 1 0 3

0.7Drowsiness 0.6 0 2

0.5Depression 0.6 0.5 12 9 Dreaming 0 0 3 1 GASTROINTESTINAL Diarrhea 2 0 3 2 Nausea 4 1 3 1 RESPIRATORY (see WARNINGS ) Wheeziness 0 0 3 3 Dyspnea 0.6 1 6 4 During postmarketing experience, the following have been reported in temporal relationship to the use of the drug: elevated liver enzymes and/or bilirubin, hallucinations, headache, impotence, Peyronie’s disease, postural hypotension which may be associated with syncope, psoriasiform rash or exacerbation of psoriasis, psychoses, purpura, reversible alopecia, thrombocytopenia, visual disturbance, sick sinus syndrome, and dry mouth.

Atenolol, like other beta-blockers, has been associated with the development of antinuclear antibodies (ANA), lupus syndrome, and Raynaud’s phenomenon. Chlorthalidone Cardiovascular: orthostatic hypotension; Gastrointestinal: anorexia, gastric irritation, vomiting, cramping, constipation, jaundice (intrahepatic cholestatic jaundice), pancreatitis; CNS: vertigo, paresthesia, xanthopsia; Hematologic: leukopenia, agranulocytosis, thrombocytopenia, aplastic anemia; Hypersensitivity: purpura, photosensitivity, rash, urticaria, necrotizing angiitis (vasculitis) (cutaneous vasculitis), Lyell’s syndrome (toxic epidermal necrolysis); Miscellaneous: hyperglycemia, glycosuria, hyperuricemia, muscle spasm, weakness, restlessness.

Clinical trials of atenolol and chlorthalidone conducted in the United States (89 patients treated with atenolol and chlorthalidone) revealed no new or unexpected adverse effects.

🔄 Drug Interactions ~1 min read

Drug Interactions Atenolol and chlorthalidone may potentiate the action of other antihypertensive agents used concomitantly. Patients treated with atenolol and chlorthalidone plus a catecholamine depletor (e.g., reserpine) should be closely observed for evidence of hypotension and/or marked bradycardia which may produce vertigo, syncope or postural hypotension. Calcium channel blockers may also have an additive effect when given with atenolol and chlorthalidone.

(See WARNINGS . ) Disopyramide is a Type I antiarrhythmic drug with potent negative inotropic and chronotropic effects. Disopyramide has been associated with severe bradycardia, asystole and heart failure when administered with beta-blockers. Amiodarone is an antiarrhythmic agent with negative chronotropic properties that may be additive to those seen with beta-blockers.

Thiazides may decrease arterial responsiveness to norepinephrine. This diminution is not sufficient to preclude the therapeutic effectiveness of norepinephrine. Thiazides may increase the responsiveness to tubocurarine.

Concomitant use of prostaglandin synthase inhibiting drugs, e.g., indomethacin, may decrease the hypotensive effects of beta-blockers. Lithium generally should not be given with diuretics because they reduce its renal clearance and add a high risk of lithium toxicity. Read prescribing information for lithium preparations before use of such preparations with atenolol and chlorthalidone.

Beta-blockers may exacerbate the rebound hypertension which can follow the withdrawal of clonidine. If the two drugs are coadministered, the beta-blocker should be withdrawn several days before the gradual withdrawal of clonidine. If replacing clonidine by beta-blocker therapy, the introduction of beta-blockers should be delayed for several days after clonidine administration has stopped.

While taking beta-blockers, patients with a history of anaphylactic reaction to a variety of allergens may have a more severe reaction on repeated challenge, either accidental, diagnostic or therapeutic. Such patients may be unresponsive to the usual doses of epinephrine used to treat the allergic reaction. Both digitalis glycosides and beta-blockers slow atrioventricular conduction and decrease heart rate.

Concomitant use can increase the risk of bradycardia.

🧒 Pediatric Use 12 words

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

🧓 Geriatric Use 83 words

Geriatric Use Clinical studies of atenolol and chlorthalidone did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant disease or other drug therapy.

🆘 Overdosage ~1 min read

OVERDOSAGE No specific information is available with regard to overdosage and atenolol and chlorthalidone in humans. Treatment should be symptomatic and supportive and directed to the removal of any unabsorbed drug by induced emesis, or administration of activated charcoal. Atenolol can be removed from the general circulation by hemodialysis.

Further consideration should be given to dehydration, electrolyte imbalance and hypotension by established procedures. Atenolol Overdosage with atenolol has been reported with patients surviving acute doses as high as 5 g. One death was reported in a man who may have taken as much as 10 g acutely.

The predominant symptoms reported following atenolol overdose are lethargy, disorder of respiratory drive, wheezing, sinus pause, and bradycardia. Additionally, common effects associated with overdosage of any beta-adrenergic blocking agent are congestive heart failure, hypotension, bronchospasm, and/or hypoglycemia. Other treatment modalities should be employed at the physician’s discretion and may include: BRADYCARDIA: Atropine 1 mg to 2 mg intravenously.

If there is no response to vagal blockade, give isoproterenol cautiously. In refractory cases, a transvenous cardiac pacemaker may be indicated. Glucagon in a 10 mg intravenous bolus has been reported to be useful.

If required, this may be repeated or followed by an intravenous infusion of glucagon 1 mg/h to 10 mg/h depending on response. HEART BLOCK (SECOND OR THIRD DEGREE): Isoproterenol or transvenous pacemaker. CONGESTIVE HEART FAILURE: Digitalize the patient and administer a diuretic.

Glucagon has been reported to be useful. HYPOTENSION: Vasopressors such as dopamine or norepinephrine (levarterenol). Monitor blood pressure continuously.

BRONCHOSPASM: A beta 2 -stimulant such as isoproterenol or terbutaline and/or aminophylline. HYPOGLYCEMIA: Intravenous glucose. ELECTROLYTE DISTURBANCE: Monitor electrolyte levels and renal function.

Institute measures to maintain hydration and electrolytes. Based on the severity of symptoms, management may require intensive support care and facilities for applying cardiac and respiratory support. Chlorthalidone Symptoms of chlorthalidone overdose include nausea, weakness, dizziness and disturbances of electrolyte balance.

🧬 Clinical Pharmacology ~3 min read

CLINICAL PHARMACOLOGY Atenolol and Chlorthalidone Atenolol and chlorthalidone have been used singly and concomitantly for the treatment of hypertension. The antihypertensive effects of these agents are additive, and studies have shown that there is no interference with bioavailability when these agents are given together in the single combination tablet. Therefore, this combination provides a convenient formulation for the concomitant administration of these two entities.

In patients with more severe hypertension, atenolol and chlorthalidone may be administered with other antihypertensives such as vasodilators. Atenolol Atenolol is a beta 1 -selective (cardioselective) beta-adrenergic receptor blocking agent without membrane stabilizing or intrinsic sympathomimetic (partial agonist) activities. This preferential effect is not absolute, however, and at higher doses, atenolol inhibits beta 2 -adrenoreceptors, chiefly located in the bronchial and vascular musculature.

Pharmacodynamics In standard animal or human pharmacological tests, beta-adrenoreceptor blocking activity of atenolol has been demonstrated by: (1) reduction in resting and exercise heart rates and cardiac output, (2) reduction of systolic and diastolic blood pressure at rest and on exercise, (3) inhibition of isoproterenol induced tachycardia and (4) reduction in reflex orthostatic tachycardia. A significant beta-blocking effect of atenolol, as measured by reduction of exercise tachycardia, is apparent within one hour following oral administration of a single dose.

This effect is maximal at about 2 to 4 hours and persists for at least 24 hours. The effect at 24 hours is dose related and also bears a linear relationship to the logarithm of plasma atenolol concentration. However, as has been shown for all beta-blocking agents, the antihypertensive effect does not appear to be related to plasma level.

In normal subjects, the beta 1 -selectivity of atenolol has been shown by its reduced ability to reverse the beta 2 -mediated vasodilating effect of isoproterenol as compared to equivalent beta-blocking doses of propranolol. In asthmatic patients, a dose of atenolol producing a greater effect on resting heart rate than propranolol resulted in much less increase in airway resistance. In a placebo controlled comparison of approximately equipotent oral doses of several beta-blockers, atenolol produced a significantly smaller decrease of FEV 1 than nonselective beta-blockers, such as propranolol and unlike those agents did not inhibit bronchodilation in response to isoproterenol.

Consistent with its negative chronotropic effect due to beta blockade of the SA node, atenolol increases sinus cycle length and sinus node recovery time. Conduction in the AV node is also prolonged. Atenolol is devoid of membrane stabilizing activity, and increasing the dose well beyond that producing beta blockade does not further depress myocardial contractility.

Several studies have demonstrated a moderate (approximately 10%) increase in stroke volume at rest and exercise. In controlled clinical trials, atenolol given as a single daily dose, was an effective antihypertensive agent providing 24-hour reduction of blood pressure. Atenolol has been studied in combination with thiazide-type diuretics and the blood pressure effects of the combination are approximately additive.

Atenolol is also compatible with methyldopa, hydralazine and prazosin, the combination resulting in a larger fall in blood pressure than with the single agents. The dose range of atenolol is narrow, and increasing the dose beyond 100 mg once daily is not associated with increased antihypertensive effect. The mechanisms of the antihypertensive effects of beta-blocking agents have not been established.

Several mechanisms have been proposed and include: (1) competitive antagonism of catecholamines at peripheral (especially cardiac) adrenergic neuron sites, leading to decreased cardiac output, (2) a central effect leading to reduced…

📦 How Supplied / Storage and Handling 120 words

HOW SUPPLIED Atenolol and chlorthalidone tablets USP, 50 mg/25 mg are white, round, scored tablets imprinted with “DAN 5782” on one side and plain on the other side. Supplied in bottles of 100 (NDC 0591-5782-01). Atenolol and chlorthalidone tablets USP, 100 mg/25 mg are white, round tablets imprinted with “DAN 5783” on one side and plain on the other side.

Supplied in bottles of 100 (NDC 0591-5783-01) Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature]. Dispense in a well-closed, light-resistant container with a child-resistant closure. Protect from heat, light and moisture.

Manufactured In India By: Watson Pharma Private Limited Verna, Salcette Goa 403 722 INDIA Manufactured For: Teva Pharmaceuticals Parsippany, NJ 07054 Rev. A 3/2024

📋 Description 201 words

DESCRIPTION Atenolol and chlorthalidone tablets, USP are for the treatment of hypertension. It combines the antihypertensive activity of two agents: a beta 1 -selective (cardioselective) hydrophilic blocking agent (atenolol), and a monosulfonamyl diuretic (chlorthalidone). Atenolol, USP is Benzeneacetamide, 4-[2’-hydroxy-3’-[(1-methylethyl)amino]propoxy]-.

It has the following structural formula: C 14 H 22 N 2 O 3 M.W. 266.34 Atenolol, USP (free base) is a relatively polar hydrophilic compound with a water solubility of 26.5 mg/mL at 37°C. It is freely soluble in 1N HCl (300 mg/mL at 25°C) and less soluble in chloroform (3 mg/mL at 25°C).

Chlorthalidone, USP is 2-Chloro-5-(1-hydroxy-3-oxo-1-isoindolinyl) benzene sulfonamide. Chlorthalidone, USP has a water solubility of 12 mg/100 mL at 20°C. It has the following structural formula: C 14 H 11 ClN 2 O 4 S M.W.

338.77 Each atenolol and chlorthalidone tablet, USP 50 mg/25 mg for oral administration contains: atenolol USP, 50 mg and chlorthalidone USP, 25 mg. Each atenolol and chlorthalidone tablet, USP 100 mg/25 mg for oral administration contains: atenolol USP, 100 mg and chlorthalidone USP, 25 mg. Atenolol and chlorthalidone tablets USP, 50 mg/25 mg and 100 mg/25 mg, contain the following inactive ingredients: magnesium stearate, microcrystalline cellulose, povidone and sodium starch glycolate.

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Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.