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Verapamil

Sounds like 'ver-ap-ah-mil'

Key points about verapamil

Verapamil is used to treat high blood pressure, irregular heart beat and to prevent chest pain (angina)
Verapamil is also called Isoptin®.
Find out how to take it safely and possible side effects.

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Verapamil belongs to a group of medicines called calcium channel blockers or calcium antagonists. It doesn’t affect the amount of calcium in your blood or bones.

Verapamil is used to treat high blood pressure (hypertension) and to prevent chest pain (angina). It may help you exercise more and decrease how often you get chest pain.

Verapamil may also be used to control your heart rate if you have a fast or irregular heartbeat (such as with atrial fibrillation).

It works by relaxing blood vessels which helps to lower your blood pressure.

In Aotearoa New Zealand, verapamil is known as Isoptin® or Isoptin SR®.

It’s available as immediate-release tablets (40 mg and 80 mg) and slow release tablets (120 mg and 240 mg). It can also be given as an injection, but this is usually only done in hospital.

The dose of verapamil will be different for different people. Your healthcare provider will tell you which dose is right for you.
Verapamil is available in 2 forms – as immediate release tablets and slow release tablets. Check with your pharmacist which form you're taking.
Always take your verapamil exactly as your healthcare provider has told you. The pharmacy label on your medicine will tell you how much verapamil to take, how often to take it, and any special instructions.

Verapamil immediate release and slow release tablets are available in different strengths. If your tablets look different to your last supply ask your pharmacist about it.

Formulation	How to take it
Immediate release tablets (40 mg and 80 mg)	These are usually taken 2 or 3 times daily. Try to space your doses evenly throughout the day. Take verapamil with food. Take your tablets with a glass of water. Swallow your tablets whole. If you have trouble swallowing them, they can be crushed. Ask your pharmacist for advice.
Slow release tablets (120 mg and 240 mg)	These are usually taken once or twice daily. Take your doses at the same times each day. Take verapamil with food. Swallow the slow release tablets whole, with a glass of water. Don't crush or chew them.

Formulation

How to take it

Immediate release tablets

(40 mg and 80 mg)

These are usually taken 2 or 3 times daily.
Try to space your doses evenly throughout the day.
Take verapamil with food.
Take your tablets with a glass of water.
Swallow your tablets whole. If you have trouble swallowing them, they can be crushed. Ask your pharmacist for advice.

Slow release tablets

(120 mg and 240 mg)

These are usually taken once or twice daily.
Take your doses at the same times each day.
Take verapamil with food.
Swallow the slow release tablets whole, with a glass of water. Don't crush or chew them.

Missed dose: If you forget your dose, take it as soon as you remember. But if it’s nearly time for your next dose, just take the next dose at the usual time. Don’t take double the dose.

Here are some things to know when you're taking verapamil. Other things may be important as well, so ask your healthcare provider what you should know about.

Other medicines:
- Verapamil interacts with some medicines (eg, atorvastatin, colchicine), herbal supplements (eg, St John's Wort) and rongoā Māori, so check with your healthcare provider before starting verapamil and before starting any new products.
- Verapamil can interact with anti-inflammatories you can buy over the counter, such as diclofenac (eg, Voltaren®), ibuprofen (eg, Nurofen®), or aspirin (eg, Disprin®, in doses used for pain relief). Anti-inflammatories can also be found in some cold and flu medicines (eg, Nurofen Cold and Flu®).
Alcohol: Verapamil can make you feel tired or dizzy. Limit or avoid drinking alcohol while you're taking verapamil. Alcohol may increase these side-effects.
Keep taking verapamil regularly: Don’t stop taking verapamil suddenly; talk to your healthcare provider before stopping.
Grapefruit, grapefruit juice or sour/Seville oranges: Avoid grapefruit, grapefruit juice or foods containing grapefruit while taking verapamil. It can increase the amount of verapamil in your body. Read more about grapefruit and medicines.
Pregnancy or breastfeeding: Talk to your healthcare provider if you're pregnant, planning a pregnancy or want to breastfeed.
Monitoring: You may have blood tests to check how well your liver is working.

Like all medicines, verapamil can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Side effects	What should I do?
Constipation	Constipation is common. Eat more fruit, vegetables, brown bread, bran-based breakfast cereals and drink plenty of water to prevent constipation. If you have problems with constipation before starting verapamil, tell your doctor. You may be prescribed a laxative, which you need to take regularly.
Dizziness Feeling light-headed Feeling faint when you stand up	These are common when you first start taking verapamil and usually go away with time. Be careful when driving or using tools until you know how this medicine affects you. Be careful when getting up from either lying down or sitting to avoid falls. Avoid drinking alcohol. Tell your doctor if these bother you.
Headache Feeling sick (nausea) Being sick (vomiting) Feeling tired Feeling flushed (red in the face) Swelling of the ankles or feet	These are less common. Tell your doctor if these bother you.
Changes in your heartbeat (either too slow, too fast or irregular) Chest tightness Wheezing or trouble breathing	These are not common. Tell your doctor immediately or ring Healthline 0800 611 116.
Signs of an allergic reaction such as skin rash, itches, swelling of the face, lips, mouth and tongue or problems breathing	This is rare. Tell your doctor immediately or ring Healthline 0800 611 116.