Diezar is used alone or together with other medicines to treat angina (chest pain) and high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.
Diezar is a calcium channel blocker. It affects the movement of calcium into the cells of the heart and blood vessels. As a result, Diezar relaxes blood vessels and increases the supply of blood and oxygen to the heart while reducing its workload.
Diezar is available only with your doctor's prescription.
An indication is a term used for the list of condition or symptom or illness for which the medicine is prescribed or used by the patient. For example, acetaminophen or paracetamol is used for fever by the patient, or the doctor prescribes it for a headache or body pains. Now fever, headache and body pains are the indications of paracetamol. A patient should be aware of the indications of medications used for common conditions because they can be taken over the counter in the pharmacy meaning without prescription by the Physician.
Diezar tablets, USP 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 Diezar.
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 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.
Diezar may be used alone or in combination with other antihypertensive agents.
Coronary Artery Disease (CAD)
Chronic Stable Angina
Diezar tablets, USP are indicated for the symptomatic treatment of chronic stable angina. Diezar tablets, USP may be used alone or in combination with other antianginal agents.
Vasospastic Angina (Prinzmetal's or Variant Angina)
Diezar tablets, USP are indicated for the treatment of confirmed or suspected vasospastic angina. Diezar tablets, USP may be used as monotherapy or in combination with other antianginal agents.
Angiographically Documented CAD
In patients with recently documented CAD by angiography and without heart failure or an ejection fraction < 40%, Diezar tablets, USP are indicated to reduce the risk of hospitalization for angina and to reduce the risk of a coronary revascularization procedure.
How should I use Diezar?
Use Diezar as directed by your doctor. Check the label on the medicine for exact dosing instructions.
An extra patient leaflet is available with Diezar. Talk to your pharmacist if you have questions about this information.
Take Diezar by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
Taking Diezar at the same time each day will help you remember to take it.
Continue to take Diezar even if you feel well. Do not miss any doses.
If you miss a dose of Diezar, take it as soon as possible. If it has been more than 12 hours since you missed your last dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use Diezar.
Uses of Diezar in details
There are specific as well as general uses of a drug or medicine. A medicine can be used to prevent a disease, treat a disease over a period or cure a disease. It can also be used to treat the particular symptom of the disease. The drug use depends on the form the patient takes it. It may be more useful in injection form or sometimes in tablet form. The drug can be used for a single troubling symptom or a life-threatening condition. While some medications can be stopped after few days, some drugs need to be continued for prolonged period to get the benefit from it.
Use: Labeled Indications
Angina: Treatment of symptomatic chronic stable angina; treatment of confirmed or suspected vasospastic angina (previously referred to as Prinzmetal or variant angina). May be used alone or in combination with other antianginal agents.
Hypertension: Management of hypertension in adults and children ≥6 years of age.
Off Label Uses
Based on the European Society for Vascular Medicine guidelines for the diagnosis and management of Raynaud phenomenon, Diezar is a reasonable alternative to nifedipine for the management of this condition.
Diezar is a long-acting 1,4-dihydropyridine calcium channel blocker. It acts primarily on vascular smooth muscle cells by stabilizing voltage-gated L-type calcium channels in their inactive conformation. By inhibiting the influx of calcium in smooth muscle cells, Diezar prevents calcium-dependent myocyte contraction and vasoconstriction. A second proposed mechanism for the drug’s vasodilatory effects involves pH-dependent inhibition of calcium influx via inhibition of smooth muscle carbonic anhydrase. Some studies have shown that Diezar also exerts inhibitory effects on voltage-gated N-type calcium channels. N-type calcium channels located in the central nervous system may be involved in nociceptive signaling and pain sensation. Diezar is used to treat hypertension and chronic stable angina.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Note: A beta-blocker is the preferred initial therapy; if there are ongoing symptoms on beta-blocker therapy, a long acting dihydropyridine calcium channel blocker (eg, Diezar) may be added; Diezar may also be used as an alternative therapy if there are contraindications or unacceptable adverse effects with beta-blockade (ACC/AHA [Fihn 2012]).
5 to 10 mg once daily.
Note: May use alone or in combination with nitrates (ACC/AHA [Fihn 2012]).
5 to 10 mg once daily.
Note: For patients who warrant combination therapy (BP >20/10 mm Hg above goal or suboptimal response to monotherapy), may use with another appropriate agent (eg, angiotensin-converting enzyme [ACE] inhibitor, angiotensin II receptor blocker [ARB], or thiazide diuretic) (ACC/AHA [Whelton 2018]). For combination therapy, some experts recommend Diezar plus either an ACE inhibitor or ARB (Jamerson 2008; Mann 2019).
Initial: 2.5 to 5 mg once daily; titrate every 1 to 2 weeks as needed based on patient response; maximum: 10 mg/day (ACC/AHA [Whelton 2018]; Jamerson 2008); antihypertensive effect attenuates with higher doses and adverse effects may become more prominent (Mann 2019).
Raynaud phenomenon (off-label use):
5 mg once daily; if needed, increase dose gradually based on patient response and tolerability, usually once every 4 weeks, but not more frequently than once every 7 to 10 days; monitor blood pressure closely with each dose increase; maximum dose: 20 mg/day (ESVM [Belch 2017]; Wigley 2020).
Dosing should start at the lower end of dosing range and be titrated to response due to possible increased incidence of hepatic, renal, or cardiac impairment. Elderly patients also show decreased clearance of Diezar.
Children 1 to 5 years: Limited data available: Note: A population pharmacokinetic study found that children <6 years of age had weight-adjusted clearance and V of Diezar that were significantly greater than children ≥6 years of age. This may suggest the need for higher mg/kg/day doses in younger children (<6 years of age); however, the study included only a small number of younger children (n=11) (Flynn 2006). One retrospective pediatric study (n=55) that included only eight patients 1-6 years of age used initial doses of 0.05-0.1 mg/kg/day; doses were titrated upwards as needed; mean required dose was significantly higher in patients 1-6 years of age (0.3 ± 0.16 mg/kg/day) compared to older children (6 to 12 years: 0.16 ± 0.12 mg/kg/day; 12 to 20 years: 0.14 ± 0.1 mg/kg/day) (Flynn 2000a).
Children and Adolescents 6 to 17 years: 2.5 to 5 mg once daily; doses >5 mg daily have not been fully studied. In a randomized, placebo-controlled trial of Diezar in children (n=268; mean age: 12.1 years; range: 6 to 16 years), a significant reduction in systolic blood pressure (compared to placebo) was observed in both the 2.5 mg once daily and the 5 mg once daily Diezar groups. The authors recommend an initial dose of 0.06 mg/kg/day with a maximum dose of 0.34 mg/kg/day (not to exceed 10 mg/day) (Flynn 2004).
Diezar has been safely administered with thiazide diuretics, alpha blockers, beta-blockers, ACE inhibitors, long-acting nitrates, sublingual nitroglycerine, non-steroidal anti-inflammatory drugs, antibiotics, and oral hypoglycemic drugs.
In vitro data from studies with human plasma indicate that Diezar has no effect on protein binding of the drugs tested (digoxin, phenytoin, warfarin, or indomethacin).
Simvastatin: Co-administration of multiple doses of 10 mg Diezar with 80 mg simvastatin resulted in a 77% increase in exposure to simvastatin compared to simvastatin alone. Limit the dose of simvastatin in patients on Diezar to 20 mg daily.
Grapefruit Juice: Co-administration of 240 mL grapefruit juice with a single oral dose of 10 mg Diezar in 20 healthy volunteers had no significant effect on the pharmacokinetics of Diezar. The study did not allow examination of the effect of genetic polymorphism in CYP3A4, the primary enzyme responsible for metabolism of Diezar; therefore, administration of Diezar with grapefruit or grapefruit juice is not recommended as bioavailability may be increased in some patients, resulting in increased blood pressure lowering effects.
CYP3A4 Inhibitors: Co-administration of a 180 mg daily dose of diltiazem with 5 mg Diezar in elderly hypertensive patients (69 to 87 years of age) resulted in a 57% increase in Diezar systemic exposure. Co-administration of erythromycin in healthy volunteers (18 to 43 years of age) did not significantly change Diezar systemic exposure (22% increase in area under the concentration versus time curve [AUC]). Although the clinical relevance of these findings is uncertain, pharmacokinetic variations may be more pronounced in the elderly.
Strong inhibitors of CYP3A4 (e.g., ketoconazole, itraconazole, ritonavir) may increase the plasma concentrations of Diezar to a greater extent than diltiazem. Diezar should be used with caution when administered with CYP3A4 inhibitors.
Clarithromycin: Clarithromycin is an inhibitor of CYP3A4. There is an increased risk of hypotension in patients receiving clarithromycin with Diezar. Close observation of patients is recommended when Diezar is co-administered with clarithromycin.
CYP3A4 Inducers: There is no data available regarding the effect of CYP3A4 inducers on Diezar. Concomitant use of CYP3A4 inducers (e.g., rifampicin, hypericum perforatum) may decrease the plasma concentrations of Diezar. Diezar should be used with caution when administered with CYP3A4 inducers.
In the following studies, there were no significant changes in the pharmacokinetics of either Diezar or another drug within the study, when co-administered.
Special Studies: Effect of Other Agents on Diezar: Cimetidine: Co-administration of Diezar with cimetidine did not alter the pharmacokinetics of Diezar.
Aluminum/Magnesium (Antacid): Co-administration of aluminum/magnesium (antacid) with a single dose of Diezar had no significant effect on the pharmacokinetics of Diezar.
Sildenafil: A single 100 mg dose of sildenafil in subjects with essential hypertension had no effect on the pharmacokinetic parameters of Diezar. When Diezar and sildenafil were used in combination, each agent independently exerted its own blood pressure lowering effect.
Special Studies: Effect of Diezar on Other Agents: Atorvastatin: Co-administration of multiple 10 mg doses of Diezar with 80 mg atorvastatin resulted in no significant change in the steady-state pharmacokinetic parameters of atorvastatin.
Digoxin: Co-administration of Diezar with digoxin did not change serum digoxin levels or digoxin renal clearance in healthy volunteers.
Ethanol (Alcohol): Single and multiple 10 mg doses of Diezar had no significant effect on the pharmacokinetics of ethanol.
Warfarin: Co-administration of Diezar with warfarin did not change the warfarin prothrombin response time.
Cyclosporin: No drug interaction studies have been conducted with cyclosporin and Diezar in healthy volunteers or other populations, with the exception of renal transplant patients. Various studies in renal transplant patients report that co-administration of Diezar with cyclosporin affects the trough concentrations of cyclosporin, from no change up to an average increase of 40%. Consideration should be given for monitoring cyclosporin levels in renal transplant patients on Diezar.
Tacrolimus: There is a risk of increased tacrolimus blood levels when co-administered with Diezar. In order to avoid toxicity of tacrolimus, administration of Diezar in a patient treated with tacrolimus requires monitoring of tacrolimus blood levels and dose adjustment of tacrolimus when appropriate.
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.
Diezar has been evaluated for safety in more than 11,000 patients in U.S. and foreign clinical trials. In general, treatment with Diezar was well-tolerated at doses up to 10 mg daily. Most adverse reactions reported during therapy with Diezar were of mild or moderate severity. In controlled clinical trials directly comparing Diezar (N=1730) at doses up to 10 mg to placebo (N=1250), discontinuation of Diezar because of adverse reactions was required in only about 1.5% of patients and was not significantly different from placebo (about 1%). The most commonly reported side effects more frequent than placebo are reflected in the table below. The incidence (%) of side effects that occurred in a dose related manner are as follows:
Other adverse reactions that were not clearly dose related but were reported with an incidence greater than 1% in placebo-controlled clinical trials include the following:
For several adverse experiences that appear to be drug and dose related, there was a greater incidence in women than men associated with Diezar treatment as shown in the following table:
Male = %
Female = %
Male = %
Female = %
(N = 1218)
(N = 512)
(N = 914)
(N = 336)
The following events occurred in <1% but >0.1% of patients in controlled clinical trials or under conditions of open trials or marketing experience where a causal relationship is uncertain; they are listed to alert the physician to a possible relationship:
1These events occurred in less than 1% in placebo-controlled trials, but the incidence of these side effects was between 1% and 2% in all multiple dose studies.
Diezar therapy has not been associated with clinically significant changes in routine laboratory tests. No clinically relevant changes were noted in serum potassium, serum glucose, total triglycerides, total cholesterol, HDL cholesterol, uric acid, blood urea nitrogen, or creatinine.
In the CAMELOT and PREVENT studies, the adverse event profile was similar to that reported previously, with the most common adverse event being peripheral edema.
Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
The following postmarketing event has been reported infrequently where a causal relationship is uncertain: gynecomastia. In postmarketing experience, jaundice and hepatic enzyme elevations (mostly consistent with cholestasis or hepatitis), in some cases severe enough to require hospitalization, have been reported in association with use of Diezar.
Postmarketing reporting has also revealed a possible association between extrapyramidal disorder and Diezar.
Diezar has been used safely in patients with chronic obstructive pulmonary disease, well-compensated congestive heart failure, coronary artery disease, peripheral vascular disease, diabetes mellitus, and abnormal lipid profiles.
Hypersensitivity to Diezar or any component of the formulation.
Canadian labeling: Additional contraindications (not in US labeling): Hypersensitivity to other dihydropyridines; severe hypotension (systolic blood pressure <90 mm Hg); breastfeeding; hereditary fructose intolerance (oral solution); hyperglycerolemia or glycerol kinase deficiency (oral solution).
The results of a survey conducted on ndrugs.com for Diezar are given in detail below. The results of the survey conducted are based on the impressions and views of the website users and consumers taking Diezar. We implore you to kindly base your medical condition or therapeutic choices on the result or test conducted by a physician or licensed medical practitioners.
Consumer reported useful
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