Consumer Medicine Information
What is in this leaflet
This leaflet answers some common questions about Isoptin Injection.
It does not contain all the available information.
It does not take the place of talking to your doctor.
All medicines have risks and benefits. Your doctor has weighed the risks of you being
given Isoptin Injection against the benefits they expect it will have for you.
If you have any concerns about taking this medicine, talk to your doctor.
Keep this leaflet in a safe place.
You may need to read it again.
What Isoptin Injection is used for
Isoptin Injection is used to:
treat unusual fast heart beat
treat high blood pressure, also called hypertension
treat poor blood flow to the heart
prevent certain heart problems occurring during surgery
Your doctor may have prescribed Isoptin Injection for another reason. Ask your doctor
if you have any questions about why Isoptin Injection has been prescribed for you.
Isoptin Injection belongs to a group of medicines called calcium channel blockers
or calcium antagonists. They work by widening blood vessels which lets more blood
and oxygen reach the heart and at the same time lowers high blood pressure. Isoptin
Injection also helps control fast heart rate.
Isoptin does not change the amount of calcium in your blood or bones. Calcium in your
diet or in calcium supplements will not interfere with the way Isoptin Injection works.
Isoptin is available only with a doctor's prescription.
Isoptin Injection is not addictive.
Before you are given Isoptin Injection
When you must not be given it
You should not be given Isoptin Injection if you have an allergy to verapamil hydrochloride
or any of the ingredients listed at the end of this leaflet.
Some of the symptoms of an allergic reaction may include:
shortness of breath
wheezing or difficulty breathing
swelling of the face, lips, tongue or other parts of the body
rash, itching or hives on the skin
You should not be given Isoptin Injection if you:
have certain heart conditions (such as heart failure, very slow heart rate, heart
conduction problems, some irregular heartbeats or disease of the heart muscle).
are taking any of the following medications, or medications containing these ingredients:
Direct Oral Anticoagulants (DOACs) such as dabigatran (in certain situations)
have low blood pressure, also called hypotension.
You should not be given Isoptin Injection after the expiry date printed on the pack.
You should not be given Isoptin Injection if the packaging is torn or shows signs
If you are not sure whether you should be given Isoptin Injection, talk to your doctor.
Before you are given it
Tell your doctor if you have allergies to:
any other medicines
any other substances, such as foods, preservatives or dyes.
Tell your doctor if you are pregnant or intend to become pregnant.
Isoptin Injection is not recommended for use during pregnancy, particularly the first
6 months. If there is a need to consider Isoptin Injection during the last 3 months
of your pregnancy, your doctor will discuss with you the benefits and risks of using
Tell your doctor if you are breastfeeding or plan to breastfeed.
Isoptin Injection is not recommended while you are breastfeeding.
Tell your doctor if you have or have had any medical conditions, especially the following:
recent heart attack
any other heart condition
tumour in the head
high or low blood pressure
muscle conditions such as Duchenne muscular dystrophy, myasthenia gravis, Lambert-Eaton
If you have not told your doctor about any of the above, tell them before you are
given Isoptin Injection.
Taking other medicines
Several medicines can cause unwanted reactions if used with Isoptin.
Ask your doctor or pharmacist for advice before being given this medicine.
In particular tell your doctor if you are taking any of the following medicines:
Medicines to treat heart problems or high blood pressure:
Beta-blockers e.g. atenolol, propranolol, metoprolol, etc
Any other medicines used to control an irregular heart beat e.g. quinidine, flecainide,
Diuretics (also called fluid tablets).
Any other medicines used to control high blood pressure (especially prazosin or terazosin)
Medicines used to lower cholesterol:
Statins such as atorvastatin or simvastatin
Medicines used to treat or prevent blood clots (sometimes referred to as "blood thinners"):
Direct Oral Anticoagulants (DOACs) such as dabigatran
Medicines used to treat or prevent gout:
Colchicine or sulfinpyrazone
Medicines used to treat psychological problems:
Any medicines to treat depression, or psychosis. Such as imipramine, buspirone, midazolam
Medicines to treat epilepsy or seizures:
Phenytoin, carbamazepine, phenobarbital.
Medicines to treat or prevent organ transplant rejection:
Cyclosporin, everolimus, sirolimus, tacrolimus
Medicines used to treat infections or tuberculosis:
such as erythromycin, clarithromycin, telithromycin or rifampicin
Medicines used in surgical procedures:
General anaesthetics used for inducing sleep
Muscle relaxants e.g. dantrolene
Medicines used in the treatment of Human Immunodeficiency Virus (HIV):
Such as ritonavir.
Other medicines that may react with Isoptin Injection:
theophylline, a medicine used to treat asthma
doxorubicin, a medicine used to treat certain cancers
cimetidine, a medicine commonly used to treat stomach ulcers and reflux
glibenclamide, a medicine used to treat diabetes
Avoid alcohol while using Isoptin. You may experience greater blood pressure lowering
effects than usual.
Avoid grapefruit juice, as this may increase the blood levels of verapamil.
These medicines may be affected by Isoptin Injection, or may affect how well it works.
You may need different amounts of your medicine or you may need to take or use different
medicines. Your doctor will advise you.
This is not a complete list of medicines which may interfere with Isoptin.
Tell your doctor or pharmacist if you are taking or have recently taken any other
medicines or herbal remedies, including those obtained without a prescription from
a pharmacy, supermarket or health food shop.
How Isoptin Injection is given
How much is given
Your doctor will decide what dose you will receive. This depends on your condition
and other factors, such as your weight.
How it is given
Isoptin Injection is given as a slow injection or "drip" injection into a vein (intravenously).
The doctor will continuously check your heart rate and blood pressure while you are
being given Isoptin Injection.
Isoptin Injection must only be given by a doctor.
As Isoptin Injection is most likely given to you in hospital by a doctor, it is very
unlikely that you will receive too much.
Your doctor has information on how to recognise and treat an overdose. Ask your doctor
if you have any concerns.
While you are being given Isoptin Injection
Your doctor and nursing staff are trained to look after you while you are being given
Tell your doctor as soon as possible if you do not feel well while you are being given
Like all other medicines, Isoptin Injection may have unwanted side effects in some
people. Sometimes they are serious, most of the time they are not. You may need medical
treatment if you get some of the side effects.
Ask your doctor to answer any questions you may have.
Tell your doctor if you notice any of the following:
nervousness, dizziness, light-headedness
feeling sick, vomiting
pins and needles
muscular weakness or muscle and joint pains
buzzing, hissing, whistling, ringing or other persistent noise in the ears
unexpected secretion of breast milk
breast enlargement in men
impotence (inability to get or maintain an erection)
increased skin sensitivity to sunlight
Tell your doctor immediately if you notice any of the following:
difficulty in breathing, wheezing or coughing
rash, itching or hives on the skin
swelling of the face, lips, mouth, tongue or throat which may cause difficulty in
swallowing or breathing
swelling of the hands, ankles or feet
severe blisters and bleeding in the lips, eyes, mouth, nose and genitals (Stevens
throbbing and burning pain in the hands and feet with redness of the skin
bleeding under the skin or tissues
fast or irregular heartbeats
shortness of breath, and swelling of the feet or legs due to fluid build up
Other side effects not listed above may occur in some patients. Ask your doctor or
pharmacist for more information about side effects, as they have a more complete list
of side effects. Inform your doctor promptly about these or any other symptoms. If
the condition persists or worsens, seek medical attention.
Do not be alarmed by this list of possible side effects.
You may not experience any of them.
Tell your doctor if you notice anything that is making you feel unwell.
After using Isoptin Injection
Isoptin Injection will be stored in the pharmacy or on the ward at a temperature below
25 degrees Celsius.
This is not all the information available on Isoptin Injection. If you have any more
questions or are not sure about anything, ask your doctor or pharmacist.
What it looks like
Isoptin Injection is a clear colourless solution in a clear glass ampoule.
verapamil hydrochloride 5 mg per 2 mL
water for injections
Isoptin Injection is available in the following strength and pack:
5 mg in 2 mL, 5 x 2 mL ampoules
Isoptin ampoules are supplied by:
Mylan Health Pty Ltd
Level 1, 30 The Bond
30-34 Hickson Road
Millers Point, NSW 2000
Phone: 1800 314 527
Australian registration number: AUST R 12796
This leaflet was prepared in April 2021.