Buy Generic Calan Sr Online

Generic Calan Sr Information

Introduction

Calan Sr is a calcium‑channel blocker used primarily to control high blood pressure and to manage certain cardiac rhythm disorders. The medication contains the active compound verapamil, which belongs to the class of drugs that relax vascular smooth muscle and modulate cardiac conduction. In Hong Kong, Calan Sr is prescribed by physicians for hypertension, angina, and specific arrhythmias, and it is available through licensed pharmacies with a valid prescription. The product is marketed by AbbVie (formerly Abbott Laboratories) and is classified under the Blood Pressure medication group.

What is Calan Sr?

Calan Sr is an oral formulation of verapamil hydrochloride designed for once‑daily (sustained‑release) administration. It is a prescription‑only medicine approved by the Hong Kong Department of Health. The sustained‑release technology provides a gradual release of verapamil over 24 hours, allowing stable plasma concentrations and reducing the need for multiple daily doses.

Verapamil is also sold under well‑known brand names such as Isoptin, Verapamil Hydrochloride, and Calan (immediate‑release). Calan Sr offers the same active ingredient in a formulation that simplifies dosing schedules for patients who require long‑term blood pressure or anti‑arrhythmic therapy.

How Calan Sr Works

Verapamil belongs to the phenylalkylamine subclass of calcium‑channel blockers. It inhibits L‑type calcium channels in the smooth muscle of arteries and in the myocardial cells of the heart. By reducing calcium influx:

• Vasodilation occurs in peripheral arteries, lowering systemic vascular resistance and thereby decreasing arterial blood pressure.
• Negative inotropic and chronotropic effects reduce the force and rate of cardiac contraction, which eases myocardial oxygen demand (useful in angina) and slows abnormal electrical conduction (useful in supraventricular tachycardia).

The sustained‑release matrix of Calan Sr slows dissolution, so therapeutic plasma levels are achieved within 2‑4 hours after ingestion and maintained for most of the dosing interval. Verapamil is primarily metabolised by the hepatic CYP3A4 pathway and eliminated unchanged in the urine. The average elimination half‑life for the sustained‑release form is approximately 5–7 hours, but steady‑state concentrations are reached after 3–5 days of consistent dosing.

Conditions Treated with Calan Sr

• Essential Hypertension – High prevalence in Hong Kong, estimated at 25 % of adults aged ≥40 years. Verapamil lowers systolic and diastolic pressures when used as monotherapy or in combination with other antihypertensives.
• Chronic Stable Angina (Prinzmetal’s variant) – By decreasing myocardial oxygen consumption and improving coronary blood flow, verapamil reduces frequency of anginal attacks.
• Supraventricular Tachycardia (SVT) and Atrial Flutter – The drug’s AV‑node blocking properties help control ventricular response rates in re‑entrant tachyarrhythmias.
• Rate Control in Atrial Fibrillation – Verapamil is an alternative to beta‑blockers for patients who cannot tolerate those agents.

These indications are supported by the Hong Kong Drug Formulary and align with international guidelines (e.g., JNC 8, ESC 2023).

Patient Groups Most Likely to Benefit

• Adults with stage 1–2 hypertension who require a once‑daily regimen and have contraindications to ACE inhibitors or diuretics.
• Patients with angina who need both blood‑pressure control and anti‑ischemic therapy, especially those with contraindications to nitrates.
• Individuals with SVT or atrial fibrillation who desire rate control without beta‑blocker side‑effects such as bronchospasm.
• Elderly patients who prefer a simplified dosing schedule; the sustained‑release formulation reduces pill burden.

Calan Sr may be unsuitable for patients with severe left‑ventricular dysfunction (ejection fraction < 35 %), advanced atrioventricular block, or uncontrolled heart failure, as verapamil can depress myocardial contractility.

Risks, Side Effects, and Interactions

Common

• Dizziness or light‑headedness (due to blood‑pressure lowering)
• Peripheral edema, especially of the ankles
• Constipation or mild gastrointestinal upset
• Headache

Rare

• Bradycardia (heart rate < 50 bpm)
• Worsening of heart failure symptoms (e.g., dyspnoea, pulmonary congestion)
• Rash or mild photosensitivity

Serious

• Severe hypotension leading to syncope or organ hypoperfusion
• Life‑threatening heart block (second‑ or third‑degree AV block)
• Acute hepatic injury (rare)

Clinically Relevant Drug‑Drug Interactions

• CYP3A4 inhibitors (e.g., ketoconazole, erythromycin, diltiazem) may increase verapamil plasma concentrations, heightening risk of bradycardia and hypotension.
• CYP3A4 inducers (e.g., rifampicin, carbamazepine, St. John’s wort) can reduce efficacy.
• Beta‑blockers combined with verapamil can produce additive negative‑chronotropic effects; careful monitoring is required.
• Digoxin levels may rise when co‑administered; dose adjustment of digoxin may be necessary.
• Non‑steroidal anti‑inflammatory drugs (NSAIDs) can blunt the antihypertensive effect of verapamil.

Patients should disclose all current medications, including over‑the‑counter supplements, to their prescriber.

Practical Use: Dosing, Missed Dose, Overdose

• Initial adult dose for hypertension: 120 mg once daily (sustained‑release tablet). Dose may be titrated up to 240 mg daily based on blood‑pressure response and tolerability.
• Angina or SVT: 180 mg once daily, with possible increase to 360 mg daily in divided doses (e.g., 180 mg twice daily) if clinically indicated.
• Administration: Swallow whole with a glass of water; do not crush or chew, as this destroys the sustained‑release matrix.
• Missed dose: Take the dose as soon as remembered unless it is within 6 hours of the next scheduled dose; in that case, skip the missed tablet and resume the regular schedule. Do not double‑dose.
• Overdose: Symptoms may include severe hypotension, bradycardia, cardiac conduction disturbances, and respiratory depression. Immediate medical attention is required. Treatment is supportive; activated charcoal may be considered if ingestion is recent, and intravenous calcium gluconate can counteract cardiovascular toxicity.

Precautions: Avoid excessive alcohol, as it can potentiate hypotensive effects. Use cautiously in patients with hepatic impairment (dose reduction may be needed). Renal dysfunction does not markedly affect verapamil clearance, but monitoring is advised in end‑stage disease.

Buying Calan Sr from Our Online Pharmacy

Calan Sr can be ordered safely from our online pharmacy in Hong Kong. Our service offers:

• Affordable pricing – We source the medication near manufacturer cost, passing savings to the patient without compromising quality.
• Verified quality – All products come from licensed, reputable overseas suppliers that meet stringent Good Manufacturing Practice (GMP) standards.
• Guaranteed delivery – Discreet packaging and reliable logistics ensure you receive your medication within 7 days (express) or approximately 3 weeks (regular airmail).
• Online‑only access – For patients who face limited availability in local pharmacies or whose insurance does not cover the brand, our pharmacy broker service provides a legitimate, privacy‑respecting channel.

We operate as a pharmacy broker, collaborating with licensed pharmacies abroad to import the medication under Hong Kong’s personal import scheme. Every order is reviewed by an independent, licensed healthcare professional to confirm appropriateness, ensuring compliance with local regulations while preserving patient confidentiality.

FAQ

• Is Calan Sr covered by Hong Kong’s public health insurance schemes?
  Coverage varies across the Hospital Authority and private insurers. Most public plans list verapamil under the “essential drug” category, but reimbursement may depend on the specific formulation and prescribing physician’s justification.

• Can Calan Sr be taken with dietary supplements such as magnesium or potassium?
  Calcium‑channel blockers do not have direct pharmacokinetic interactions with magnesium or potassium supplements. However, high‑dose potassium may exacerbate peripheral edema, a known side effect of verapamil. Discuss any supplement regimen with your clinician.

• What is the difference between Calan Sr and immediate‑release verapamil tablets?
  Calan Sr releases verapamil slowly over 24 hours, allowing once‑daily dosing and more stable blood levels. Immediate‑release tablets deliver the drug within 1‑2 hours, requiring multiple daily doses and showing higher peak‑to‑trough fluctuations.

• Does Calan Sr require special storage conditions?
  Store the tablets at room temperature (15‑30 °C) in a dry place, away from direct sunlight and moisture. Do not refrigerate or freeze.

• Are there specific warning labels for Asian populations?
  Pharmacogenomic data suggest that some East Asian patients may have slower CYP3A4 metabolism, potentially leading to higher plasma concentrations. Physicians often start at the lower end of the dosing range and titrate cautiously.

• Can I import Calan Sr for personal use without a local prescription?
  Hong Kong permits personal import of prescription medicines for up to a 3‑month supply when accompanied by a valid prescription from a licensed practitioner. Our online pharmacy facilitates the prescription verification process to comply with this regulation.

• What packaging does Calan Sr arrive in when ordered online?
  Each order is sealed in tamper‑evident, discreet poly‑mailers. Inside, tablets are placed in a labelled blister pack indicating strength, quantity, and expiry date, along with a pharmacy information leaflet (Chinese and English).

• Is telemedicine accepted for prescribing Calan Sr in Hong Kong?
  Yes. Under the Hong Kong Medical Council’s telehealth guidelines, licensed physicians may issue electronic prescriptions after a virtual consultation, provided they have access to the patient’s medical history and perform a proper assessment.

• What should I do if I experience severe dizziness after taking Calan Sr?
  Sit or lie down immediately to prevent falls, and contact your healthcare provider promptly. Severe dizziness may indicate excessive hypotension and could require dose adjustment or an alternative therapy.

Glossary

Calcium‑Channel Blocker

A class of drugs that inhibit the influx of calcium ions through L‑type channels in vascular smooth muscle and cardiac tissue, leading to vasodilation and reduced cardiac contractility.

Sustained‑Release (SR) Formulation

A dosage form designed to release the active ingredient gradually over an extended period, allowing once‑daily dosing and more consistent plasma concentrations.

CYP3A4

An enzyme in the liver responsible for metabolising many pharmaceuticals, including verapamil. Inhibitors or inducers of CYP3A4 can alter drug levels.

AV‑Node Block

A type of cardiac conduction delay where the electrical impulse from the atria to the ventricles is slowed or stopped, potentially causing bradycardia.

⚠️ Disclaimer

The information provided about Calan Sr is for general knowledge only. It does not replace professional medical consultation. All treatment decisions should be made under the supervision of a qualified healthcare provider. We assume all readers are responsible adults capable of making informed decisions about their health. Our online pharmacy offers access to Calan Sr for individuals who may have limited availability through traditional pharmacies, prescription‑based insurance schemes, or who are seeking affordable generic alternatives. Always consult your doctor before starting, changing, or discontinuing any medication.