This grade answers one narrow question: how strong is the public evidence and safety record behind this drug, and how clean is its money trail and court record? It is not a verdict on whether the drug is right for you.
Diltiazem Hydrochloride Extended-Release Tablet is a nondihydropyridine calcium channel blocker indicated for: treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. It can be used alone or in combination with other antihypertensives. ( 1.1 ) improving exercise tolerance in patients with chronic stable angina. ( 1.2 ) 1.1 Hypertension Diltiazem Hydrochloride Extended-Release Tablets are indicated for the treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal 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 this drug. 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 one drug to achieve blood pressure goals. For specific advice...
Diltiazem hydrochloride extended-release tablets are contraindicated in: Patients with sick sinus syndrome except in the presence of a functioning ventricular pacemaker. Patients with second- or third-degree AV block except in the presence of a functioning ventricular pacemaker. Patients with hypotension (less than 90 mm Hg systolic). Patients who have demonstrated hypersensitivity to the drug. Patients with acute myocardial infarction and pulmonary. Sick sinus syndrome except in the presence of a functioning ventricular pacemaker. ( 4 ) Second- or third-degree AV block except in the presence of a functioning ventricular pacemaker. ( 4 ) Hypotension (less than 90 mm Hg systolic). ( 4 ) Hypersensitivity to the drug. ( 4 ) Acute myocardial infarction and pulmonary. ( 4 )
Bradycardia, second- or third- degree AV block: Monitor heart rate and rhythm. ( 5.1 ) Heart failure: Monitor for signs and symptoms. ( 5.2 ) Increased liver enzymes and acute hepatic injury. ( 5.3 ) Severe skin reactions. ( 5.4 ) 5.1 Bradycardia or AV Block Diltiazem hydrochloride extended-release tablets may cause abnormally slow heart rates or second- or third-degree AV block. Patients with sick sinus syndrome are at increased risk of bradycardia. Concomitant use of diltiazem with beta-blockers or digitalis may result in additive effects on cardiac conduction. A patient with Prinzmetal's angina developed periods of asystole (2 to 5 seconds) after a single dose of 60 mg of diltiazem [see Adverse Reactions (6) ] . Monitor for effects on heart rate and cardiac conduction. 5.2 Heart Failure Worsening of heart failure has been reported in patients with impairment of ventricular function. Experience with the use of diltiazem in combination with beta-blockers in patients with impaired ventricular function is limited. 5.3 Acute Hepatic Injury Significant elevations in liver enzymes such as alkaline phosphatase, LDH, AST (SGOT), ALT (SGPT) and signs of acute hepatic injury have been repo...
The following adverse reactions are described in greater detail, in other sections: Bradycardia and AV block [see Warnings and Precautions (5.1) ] Heart failure [see Warnings and Precautions (5.2) ] Acute hepatic injury [see Warnings and Precautions (5.3) ] Severe skin reactions [see Warnings and Precautions (5.4) ] The most common adverse reactions ( > 2% ) are lower limb edema, sinus congestion and rash in patients treated for hypertension, and lower limb edema, headache, dizziness, fatigue, bradycardia, first-degree AV block and cough in patients treated for angina. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact ScieGen Pharmaceuticals, Inc. at 1-855-724-3436 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. For the hypertension studies, the following table presents adverse reactions more common on diltiazem than on placebo (but excluding events with no plausible relationship to t...
Source: FDA SPL label for DILTIAZEM HYDROCHLORIDE (ScieGen Pharmaceuticals, Inc.), effective 20251016. Full label on DailyMed.
These are counts of reports people filed, not rates of harm. Anyone can file one, and nobody checks whether the drug was the cause. Millions of doses are taken for every report sent, so the useful part is how this drug compares with the average across all drugs.
| 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
|---|---|---|---|---|---|---|---|
| 6,510 | 6,460 | 5,345 | 5,101 | 4,536 | 4,304 | 4,246 | 2,051 |
1,615 reports blaming this drug for every million Medicare prescriptions filled, which is 0.6× the typical drug on this site. (10,467 reports in 2024–2026, against 6,482,880 Medicare fills in one year. This is the one number here that accounts for how many people take the drug.)
Source: the FDA's Adverse Event Reporting System (FAERS). Reports are voluntary and unverified. Drugs that are prescribed a lot, in the news, or in lawsuits attract more reports, so the percentages are compared with the whole database to correct for that partly, not fully.
| Date | Class | Firm | Reason |
|---|---|---|---|
| 03/2025 | Class II | Glenmark Pharmaceuticals Inc., USA | CGMP Deviations |
| 11/2024 | Class II | Glenmark Pharmaceuticals Inc., USA | cGMP Deviations: Presence of N-nitroso-Desmethyl-Diltiazem impurity above FDA recommended interim limit. |
| 11/2024 | Class II | Glenmark Pharmaceuticals Inc., USA | cGMP Deviations: Presence of N-nitroso-Desmethyl-Diltiazem impurity above FDA recommended interim limit. |
| 11/2024 | Class II | Glenmark Pharmaceuticals Inc., USA | cGMP Deviations: Presence of N-nitroso-Desmethyl-Diltiazem impurity above FDA recommended interim limit. |
| 04/2024 | Class II | Glenmark Pharmaceuticals Inc., USA | Failed Dissolution Specifications |
| 03/2024 | Class II | Glenmark Pharmaceuticals Inc., USA | Failed Dissolution Specifications: Out of Specification (OOS) was reported in test of dissolution at the 12th month time point in long term stability study. |
| 01/2023 | Class II | SUN PHARMACEUTICAL INDUSTRIES INC | Failed Impurity (Deacetyl Diltiazem Hydrochloride) specification during stability testing and failed dissolution testing at FDA laboratory. |
| 01/2019 | Class III | Valeant Pharmaceuticals North America LLC | Failed Dissolution Specifications: high out of specification results for dissolution when measuring the amount of drug released at certain time points. |
| 01/2019 | Class III | Valeant Pharmaceuticals North America LLC | Failed Dissolution Specifications: high out of specification results for dissolution when measuring the amount of drug released at certain time points. |
| 01/2019 | Class III | Valeant Pharmaceuticals North America LLC | Failed Dissolution Specifications: high out of specification results for dissolution when measuring the amount of drug released at certain time points. |
| 01/2019 | Class III | Valeant Pharmaceuticals North America LLC | Failed Dissolution Specifications: high out of specification results for dissolution when measuring the amount of drug released at certain time points. |
Class I = reasonable probability of serious harm. Class II = temporary or reversible harm. Class III = unlikely to harm. Most generic recalls are manufacturing or labeling defects for one lot, not a verdict on the molecule.
Counts measure how much evidence exists and how transparent it is, not how big the benefit is. For that, ask your prescriber: if 100 people like me took this, how many would get better because of it, and how many would be harmed? (Doctors call these the "number needed to treat" and "number needed to harm.") It differs by condition and is the number drug ads leave out. Sources: PubMed, ClinicalTrials.gov.
In 2024, drug companies reported $0 in payments to US physicians and hospitals tied to this drug across 0 transactions.
No pending federal MDL names this drug or its brands.
Not named in any federal pharmaceutical settlement of $100M or more on record.
Sources: CMS Open Payments (Sunshine Act); Judicial Panel on Multidistrict Litigation pending docket list; DOJ settlements as tabulated on Wikipedia with links to the primary record. State-court and individual suits are not included.
| Product | Fills | $/fill |
|---|---|---|
| Diltiazem 24hr ER (Cd) | 3,662,791 | $28 |
| Diltiazem HCl | 707,541 | $24 |
| Diltiazem 24hr ER | 629,074 | $32 |
| Dilt-XR | 383,212 | $36 |
| Cartia Xt | 258,636 | $29 |
| Diltiazem 24hr ER (XR) | 209,383 | $37 |
| Tiadylt ER | 200,287 | $32 |
| Diltiazem 12hr ER | 189,166 | $172 |
Same ATC pharmacological class, graded ones first, best grade at the top. Being in the same class does not make them interchangeable for your condition; it makes them worth asking about.