Isoptin SR (Verapamil)

Prescription Prescription Required     Customer Reviews
Isoptin SR Brand
Dosage Quantity & Price
Verapamil (Generic alternate to Isoptin SR) Generic
Dosage Quantity & Price
  • We are Certified
  • Cipa Certified Canadian
  • Norton Shopping Guarantee
  • 5 Star Excellence award from Shopper Approved for collecting at least 100 5 star reviews

Table of contents:

Isoptin SR (generically known as Verapamil) is an oral medication used to treat high blood pressure, angina, and irregular heartbeats. It belongs to the class of medications called calcium channel blockers or calcium antagonists. It works by relaxing the muscles of the heart and blood vessels, which helps to lower blood pressure and improve blood flow.

Isoptin SR is available in sustained-release oral tablets containing 120 mg or 240 mg verapamil hydrochloride. Note, the medication should only be taken as directed by a healthcare professional.

Use and Dosage

Isoptin SR (Verapamil) is a medication that can be taken orally as film-coated tablets. It is usually prescribed to be taken once daily in the morning, or every 12 hours as directed by a doctor. Take the tablet with a meal and swallow it whole with a glass of water. Chewing, crushing, or cutting the medication is not recommended as it may cause the active ingredients to be released at once, which can increase the risk of side effects.

The recommended dosages of Verapamil vary depending on the condition being treated and the form of the medication being used. For example, the typical dose for hypertension in adults ranges from 80-120mg orally every 8 hours, while the usual dose for angina after a heart attack using slow-release tablets is 360mg split into 2-3 doses per day. Follow the specific dosing instructions provided by your doctor or pharmacist.

Take Verapamil tablet exactly as prescribed by the doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Side Effects

Common Side Effects of Isoptin SR (Verapamil):

  • Constipation
  • Dizziness
  • Flushing
  • Headache
  • Lightheadedness
  • Nausea
  • Slow heartbeat
  • Tiredness

Serious Side Effects of Isoptin SR (Verapamil):

  • Blurred vision
  • Difficulty breathing or swallowing
  • Extreme tiredness
  • Fainting
  • Fever
  • Flu-like symptoms
  • Lack of energy
  • Loss of appetite
  • Nausea
  • Pain in the upper right part of the stomach
  • Rash
  • Slow heartbeat
  • Swelling of the hands, feet, ankles, or lower legs
  • Unusual bleeding or bruising
  • Yellowing of the skin or eyes

Forms and Strength

Isoptin SR (Verapamil) is available in the following forms and strength:

Isoptin SR: Prolonged Release Tablet

  • 120 mg
  • 240 mg

Verapamil: 12hour ER (Extended Release) Tablet

  • 120 mg
  • 180 mg
  • 240 mg


  • Before taking Isoptin SR, you should inform your healthcare provider about any medical conditions you have, such as liver or kidney disease, heart disease, low blood pressure, or a history of stroke.
  • You should also inform your healthcare provider about any medications you are taking, including prescription, over the counter, and herbal products, as certain medications may interact with Isoptin SR.
  • Isoptin SR may cause dizziness or lightheadedness, especially when standing up from a sitting or lying position. You should be cautious when performing activities that require alertness until you know how the medication affects you.
  • Isoptin SR may interact with certain foods or drinks, such as grapefruit juice, which can increase the risk of side effects.
  • If you are pregnant or breastfeeding, you should talk to your healthcare provider before taking Isoptin SR, as its safety in these populations has not been established.
  • Isoptin SR may affect your heart rate and rhythm. You should inform your healthcare provider if you experience any symptoms of a slow or irregular heartbeat, such as palpitations, shortness of breath, or fainting.
  • Isoptin SR may interact with certain medications used for anesthesia or surgery, such as neuromuscular blocking agents, which can increase the risk of side effects.
  • Isoptin SR may cause constipation, especially in elderly patients. You should ensure you stay hydrated and consume high-fibre foods to help manage this side effect.
  • If you have diabetes, Isoptin SR may affect your blood sugar levels. You should monitor your blood sugar closely while taking the tablet.
  • Isoptin SR is not recommended for use in children under 18 years old.

Frequently Asked Questions (FAQ)

How long does it typically take for Isoptin SR (Verapamil) to start working?

It can take several weeks for Isoptin SR (Verapamil) to reach its full effectiveness in controlling blood pressure and relieving symptoms of angina and other heart conditions.

Can Isoptin SR (Verapamil) be used to treat migraines?

Yes, Isoptin SR (Verapamil) may be used to prevent migraines in some cases. However, talk to your doctor about the risks and benefits of this treatment, as well as other possible options for migraine prevention.

Is it safe to drink alcohol while taking Isoptin SR (Verapamil)?

Do not drink alcohol while taking Isoptin SR (Verapamil), as it can increase the risk of side effects such as dizziness, lightheadedness, and low blood pressure.

Can Isoptin SR (Verapamil) cause weight gain?

Weight gain is not a common side effect of Isoptin SR (Verapamil), but it may occur in some individuals. If you experience unexplained weight gain while taking the tablet, talk to your doctor.

How long should you continue taking Isoptin SR (Verapamil)?

Continue taking Isoptin SR (Verapamil) as prescribed by your doctor, even if you start feeling better. Suddenly stopping the medication can lead to a rapid increase in blood pressure or other complications.


It's important to purchase Isoptin SR from verified Canadian pharmacy.

Additional information

Generic name:

Verapamil, Verapamil ER


12hour ER Tablet, Extended Release Tablet, Prolonged Release Tablet


120mg, 180mg, 240mg

Quantities Available: