Isoptin SR® sustained‑release verapamil for hypertension and angina

What Isoptin SR® Is and How It Works

Isoptin SR is the sustained‑release form of verapamil, a calcium channel blocker used to treat high blood pressure and chronic stable angina. It reduces calcium entry into heart and vascular smooth muscle cells. This lowers peripheral resistance, eases cardiac workload, and helps control heart rate and atrioventricular conduction. Many people use once‑daily dosing. Common strengths include Isoptin SR 120, Isoptin SR 180 mg, and Isoptin SR 240 mg. If you need Isoptin SR without insurance, Canadian pricing may help your monthly budget. Examples such as Isoptin SR 240 mg tablets are often chosen for once‑daily control.

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Isoptin SR is indicated for hypertension and for reducing angina frequency. Your prescriber may also use it for rate control in certain supraventricular arrhythmias. The sustained‑release matrix releases verapamil over many hours. Steady levels support smoother 24‑hour blood pressure coverage and fewer peak‑trough swings compared with immediate‑release tablets.

Dosage and Usage

• Hypertension, typical start: 120–180 mg once daily. Some start at 120 mg if older or sensitive.
• Titration: increase by 60–120 mg at 7–14‑day intervals based on response.
• Usual range: 180–360 mg per day. Max dose often 480 mg per day.
• Angina, typical total: 240–480 mg per day in one or two daily doses, as directed.
• Take at the same time each day, preferably with food for steady absorption.
• Swallow sustained‑release tablets whole. Do not crush or chew.
• Do not split unless your pharmacist confirms your specific brand is scored and splitting will not affect release.
• Missed dose: take when remembered unless it is near the next dose. Do not double the dose.
• Avoid grapefruit and grapefruit juice. They can raise verapamil levels.
• Limit alcohol. It can enhance blood pressure‑lowering effects and dizziness.

• Store at 15–25 °C (59–77 °F); short trips up to 30 °C (86 °F) are acceptable.
• Keep tablets in the original container with the lid closed to protect from moisture.
• Store away from sunlight and heat sources; do not keep in bathrooms.
• For travel, carry your medicine in hand luggage with a copy of your prescription.
• Pack enough for the whole trip, plus a few extra days for delays.
• Do not leave medicine in a parked car or near windows.

Benefits and Savings

Isoptin SR provides steady 24‑hour blood pressure control with a convenient daily schedule. Sustained‑release verapamil may reduce peak‑related side effects seen with immediate‑release forms. Many patients see fewer angina episodes and improved exercise tolerance as the dose stabilizes. The tablet strengths make dose adjustments straightforward, including Isoptin SR 180 mg and Isoptin SR 240 mg options.

Ordering from Canada can lower your Isoptin SR price. Typical savings are 60–80% versus many US retail prices. If you pay cash, your Isoptin SR cash price through our pharmacy can be budget‑friendly, even without insurance. Multi‑month supplies often reduce the per‑month cost, and bulk promotions may apply to commonly used strengths such as Isoptin 240 SR.

For periodic offers, you can check any current Isoptin SR coupon.

Side Effects and Safety

• Constipation
• Dizziness or lightheadedness
• Headache
• Nausea or upset stomach
• Fatigue
• Flushing
• Slow heart rate
• Swollen ankles or feet (peripheral edema)
• Low blood pressure, especially when standing

Serious but less common risks include heart block, worsening heart failure, fainting, severe hypotension, or liver enzyme elevations. Rare effects include allergic reactions or gingival overgrowth. Do not use in certain conduction disorders (such as second‑ or third‑degree AV block or sick sinus syndrome) unless a pacemaker is present. Use caution if you have reduced ejection fraction heart failure. Important interactions include beta‑blockers, digoxin, lithium, and CYP3A modulators; verapamil can raise levels of drugs like simvastatin. Avoid grapefruit products.

Onset Time

Blood pressure may start to improve within one week of starting or changing dose. Full effect can take 2–4 weeks as the dose and steady‑state levels are optimized. Angina frequency often decreases during the first one to two weeks. Constipation and dizziness, if they occur, may appear early and often lessen with time, dose adjustment, or supportive measures advised by your clinician.

Compare With Alternatives

Verapamil is also available as a lower‑cost generic. If your prescriber approves, generic sustained‑release tablets may offer the same active ingredient at a lower price. You can compare availability on Verapamil pages and select strengths that match your prescription.

Beta‑blockers such as Bystolic® lower heart rate and blood pressure through a different pathway. They can be helpful when heart rate control is a priority or when calcium channel blockers are not tolerated. They may cause fatigue or sexual side effects in some patients and require heart rate monitoring.

Angiotensin receptor blockers like Micardis® relax blood vessels without direct effects on heart rate. They are often combined with other antihypertensives and may be preferred in some comorbid conditions. Each option has distinct profiles for cough risk, edema, or heart‑rate effects. Your prescriber will match therapy to your goals and health history.

Combination Therapy

• With ACE inhibitors or ARBs: common in hypertension for additive blood pressure control.
• With thiazide diuretics: useful step‑up in resistant hypertension.
• With beta‑blockers: possible in selected cases; monitor for bradycardia or heart block and consider lower doses.
• With nitrates for angina: may reduce attack frequency and improve exercise tolerance.
• With statins: prefer lower simvastatin doses or use alternatives to reduce interaction risk.
• With digoxin: monitor levels; verapamil can increase digoxin exposure.

Patient Suitability and Cost-Saving Tips

Isoptin SR can suit adults who need steady blood pressure reduction or angina control and who benefit from once‑daily dosing. It may not suit those with very low blood pressure, certain conduction abnormalities, recent myocardial infarction with pulmonary congestion, or decompensated heart failure. People with liver impairment may need dose adjustments. Older adults may start at lower doses, such as 120 mg once daily, with careful titration.

Drug interactions are important. Tell your prescriber about beta‑blockers, antiarrhythmics, digoxin, certain antibiotics or antifungals, antiretrovirals, anticonvulsants, and statins. Avoid grapefruit products. Alcohol can intensify dizziness and hypotension. Do not stop or change your dose without medical guidance. For tablets, do not crush or chew sustained‑release forms. Ask your pharmacist before splitting to keep the release profile intact.

To manage costs, consider 90‑day supplies when appropriate. This can lower the monthly Isoptin SR 240 cost compared with smaller fills. Set reorder reminders so you do not run out. If you are paying the Isoptin SR no insurance rate, compare strengths like Isoptin 240 and Isoptin 240 mg tablets to find the most economical pack size your prescription allows.

Authoritative Sources

Health Canada Drug Product Database (verapamil, sustained‑release)

DailyMed labels for verapamil extended‑release tablets

FDA Drug Database search for verapamil

Order Isoptin SR® from Youdrugstore.com: add to cart, upload your prescription, and we ship with prompt, express, cold‑chain handling.

This material is educational and does not replace medical advice from your healthcare professional. Always follow your prescriber’s directions for your specific condition.