Basic Verapamil Information

• INN (International Nonproprietary Name): Verapamil
• Brand Names Available in Australia: Calan, Isoptin, Verapamil Arena
• ATC Code: C08DA01
• Forms & Dosages: Tablets (40 mg, 80 mg, 120 mg), Extended-release tablets (240 mg), IV solution (2.5 mg/mL)
• Manufacturers in Australia: Abbott, Pfizer, Mylan, Sandoz, Teva
• Registration Status in Australia: Prescription only (Rx)
• OTC / Rx Classification: Rx (Prescription only)

Latest Research Highlights

Recent studies in both Australia and globally have focused on the efficacy and safety of verapamil across different patient demographics. Research conducted from 2022 to 2025 indicates promising outcomes in managing hypertension and supraventricular arrhythmias. A recent randomised control trial highlighted that verapamil significantly reduces hospitalisation rates for heart failure patients compared to other calcium channel blockers, such as amlodipine (Cannon et al., 2023). In Australia, the Therapeutic Goods Administration (TGA) monitors ongoing studies to ensure strict adherence to safety protocols.

Tables summarised below illustrate patient outcomes from various studies concerning efficacy, side effects, and comparative analysis with alternatives, like amlodipine. The data not only supports verapamil's role in managing serious health conditions but also highlights its safety profile, making it a preferred medication among clinicians.

Overall, the current evidence confirms verapamil's efficacy and examines its mechanism of action, establishing it as a key player in cardiac therapy while also exploring its potential off-label uses.

Composition & Brand Landscape

Verapamil is a versatile medication available in various formulations and strengths tailored to meet the diverse needs of Australian patients. The active ingredient in these products is verapamil hydrochloride.

Several established brands dominate the market, including Calan and Isoptin, alongside generics like verapamil arena. These options can be found in different dosage forms, notably:

• Tablets: 40 mg, 80 mg, and 120 mg.
• Extended-release formulations: 120 mg, 180 mg, and 240 mg.
• Injectable solutions: 2.5 mg/mL (2 mL ampoules).

The Pharmaceutical Benefits Scheme (PBS) includes verapamil on its list of subsidised medications. This helps ensure that patients across Australia, particularly the elderly, can access this vital treatment while saving on costs. Major pharmacy chains like Chemist Warehouse and Priceline provide extensive availability of various verapamil formulations, enhancing access to patients in both urban and rural settings.

The rise of generics has stirred up competition in the market, leading to more affordable choices for consumers. This trend aligns with the Australian culture's price-sensitive shopping habits. Health professionals regularly engage with patients to discuss available brands, improving their understanding and confidence in their treatment plans.

This accessibility and variety ensure patients can find the formulation that best suits their needs, allowing a more personalised approach to treatment.

Contraindications & Special Precautions

The use of verapamil necessitates strict attention to contraindications to protect patient safety. Some absolute contraindications include:

• Severe hypotension (systolic <90 mmHg)
• Advanced AV block
• Significant left ventricular dysfunction.

There are important precautions for specific groups as well. Elderly patients or those with renal and hepatic impairment require careful monitoring when prescribed verapamil.

Education regarding daily-life restrictions is vital. Patients may face limitations on driving or operating machinery due to potential side effects like dizziness and hypotension. For communities such as the Aboriginal and Torres Strait Islander people, it is critical for healthcare approaches to be tailored, promoting better understanding and adherence to medicine regimens.

Dosage Guidelines

Dosage for verapamil hinges on the condition being treated. Commonly, for hypertension, initial dosing begins at 80-120 mg taken three times daily, with a maximum daily dosage of up to 480 mg. For off-label indications such as migraines, a sustained-release dosage of 240 mg is often recommended.

The adjustment of dosages according to patient profiles keeps treatment safe and effective. Particularly for the elderly and those with hepatic dysfunction, it’s advisable to start at the lower end of the dosage spectrum to minimise the risk of side effects.

In conclusion, it is crucial for healthcare professionals to stay well-informed about verapamil dosing and to ensure they provide guidance that caters to individual patient needs. Regular reassessment of doses helps optimise the patient’s treatment journey and can lead to better health outcomes.

Interactions Overview

The risk of interactions with verapamil necessitates vigilant patient management. Concerns regarding the interplay of medications and lifestyle choices can often leave patients confused or anxious.

Alcohol consumption is a primary example of how interactions can complicate treatment. It can exacerbate the effects of verapamil, leading to increased drowsiness and hypotension. To mitigate these risks, patients are typically advised to limit or closely monitor their alcohol intake while undergoing treatment.

When looking at drug interactions, several notable combinations require attention. Concurrent use with beta-blockers can heighten the risk of bradycardia and heart block, which can present as warning signs. These critical risks must be clearly communicated by healthcare providers to patients.

Additionally, grapefruit juice poses a unique challenge, as it can hinder the metabolism of verapamil. This interference might lead to adverse effects or unintentional overdosing, further complicating a patient's medication regimen.

A comprehensive assessment of a patient's current medication regimen is vital to avoid these complications. Healthcare professionals can utilise resources like TGA’s Electronic Health Records to effectively analyse interactions, ensuring patient safety throughout treatment protocols.

Pharmacy Availability and Delivery

Verapamil is widely accessible in pharmacies across Australia, often available without a prescription. This availability makes it easier for patients to obtain the necessary medication. Below is an overview of major cities and their respective delivery times for verapamil: