Consumer medicine information


Diltiazem hydrochloride

Consumer Medicine Information

What is in this leaflet

This leaflet answers some common questions about Dilzem CD capsules.

It does not contain all the available information. This leaflet does not take the place of talking to your doctor or pharmacist.

All medicines have risks and benefits. Your doctor has weighed the risks to you of taking Dilzem CD capsules against the benefits the medicine is expected to have for you.

If you have any concerns about taking this medicine, talk to your doctor or pharmacist.

Keep this leaflet with the medicine. You may need to read it again.

What Dilzem CD capsules are used for

Dilzem CD capsules contain an active ingredient called diltiazem hydrochloride. They are designed to release the active ingredient over 24 hours and can be taken once a day (CD stands for “controlled delivery”). Dilzem belongs to a group of medicines known as calcium channel blockers or calcium antagonists. These medicines work by opening up blood vessels, which lowers blood pressure and lets more blood and oxygen reach the heart. They do not change the amount of calcium in your blood or bones.

Dilzem CD capsules are used by some people to treat hypertension (high blood pressure), by others to prevent angina and by some people to treat both of these conditions at the same time.


Angina is a pain or uncomfortable feeling in the chest, often spreading to the arms and neck, and sometimes the shoulders and back. This may be caused by not enough blood and oxygen getting to the heart. Angina is usually brought on by exercise or stress.


Everyone has blood pressure. This pressure helps move your blood around your body. Your blood pressure may be different at different times of the day, depending on how busy or worried you are. You have hypertension (high blood pressure) when your blood pressure stays higher than is needed, even when you are calm and relaxed. There are usually no symptoms of hypertension. The only way of knowing that you have hypertension is to have your blood pressure checked on a regular basis. You may feel fine and have no symptoms, but if high blood pressure is not treated, it can lead to serious health problems. Your doctor may have prescribed Dilzem CD capsules for another reason.

Ask your doctor if you have any questions about why Dilzem CD capsules have been prescribed for you. There is no evidence that Dilzem CD capsules are addictive. This medicine is available only with a doctor’s prescription.

Before you take Dilzem CD capsules

When you must not take it

Do not take Dilzem CD capsules if you have had an allergy to diltiazem or any of the ingredients listed at the end of this leaflet.

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
  • hives, itching or skin rash.

Do not take Dilzem CD capsules if you have had an allergy to any other calcium channel blocker medicine. Do not take Dilzem CD capsules if you have any of the following medical conditions:

  • heart conditions such as sick sinus syndrome or second or third degree atrioventricular block (unless you have a pacemaker)
  • hypotension
  • congestive heart failure

Do not take Dilzem CD capsules if the packaging is torn or shows signs of tampering . Do not take Dilzem CD capsules after the expiry date (EXP) printed on the pack. If you take this medicine after the expiry date has passed, it may not work as well.

Do not give Dilzem CD capsules to a child unless directed by your child’s doctor. The safety and efficacy of Dilzem CD capsules in children have not been established. Therefore their use in children is not recommended.

Before you start to take it

Tell your doctor or pharmacist if you have allergies to:

  • any other medicines
  • any other substances such as preservatives, foods, or dyes

Tell your doctor or pharmacist if you are pregnant or intend to become pregnant. Like most calcium channel blocker medicines, diltiazem is not recommended for use during pregnancy.

Tell your doctor or pharmacist if you are breast-feeding or plan to breast-feed. Diltiazem passes into breast milk. There is a possibility that the breast-fed baby may be affected.

Tell your doctor or pharmacist if you have or have had any medical conditions, especially the following:

  • kidney or liver disease
  • diabetes
  • other heart conditions

If you have not told your doctor or pharmacist about any of the above, tell them before you start taking Dilzem CD capsules.

Taking other medicines

Tell your doctor or pharmacist if you are taking any other medicines, including any that you buy without a prescription from your pharmacy, supermarket or health food shop. Some medicines and Dilzem CD capsules may interfere with each other. These include:

  • beta-blockers such as propranolol or atenolol
  • digoxin (a medicine used to treat heart failure)
  • cimetidine (a medicine used to treat reflux and stomach ulcers)
  • diazepam (a medicine used to treat anxiety)
  • cyclosporin (a medicine used to suppress the immune system)
  • amiodarone (a medicine used to treat irregular heart beats)
  • inhalation anaesthetics such as isoflurane
  • medicines for angina, such as glyceryl trinitrate or isosorbide dinitrate.
  • simvastatin or lovastatin (medicines used for lowering blood cholesterol).

These medicines may be affected by Dilzem CD capsules, or they may affect how well your Dilzem CD capsules work. You may need different amounts of your medicine, or you may need to take different medicines. Your doctor or pharmacist will advise you. Your doctor or pharmacist may have more information on medicines to be careful with or avoid while taking Dilzem CD capsules.

How to take Dilzem CD capsules

How much to take

Dilzem CD capsules should be taken once a day, preferably at the same time every day. Your doctor will tell you how often and how much to take.

Follow all directions given to you by your doctor or pharmacist carefully. They may differ from the information contained in this leaflet. If you do not understand the instructions on the label, ask your doctor or pharmacist for help.

How to take it

Swallow the capsules with a full glass of water. Do not chew the capsules.

When to take it

Take Dilzem CD capsules at about the same time each day. Taking this medicine at the same time each day will have the best effect. It will also help you remember when to take your medicine. It does not matter if you take Dilzem CD capsules before or after food.

How long to take it

Dilzem CD capsules help control your angina and/or blood pressure but do not cure it. Therefore Dilzem CD capsules must be taken every day. Continue taking Dilzem CD capsules for as long as your doctor tells you to.

Do not stop taking Dilzem CD capsules without first checking with your doctor.

If you are taking Dilzem CD capsules for angina, your doctor may wish to gradually reduce the amount of medicine you are taking before stopping completely. This may help reduce the chance of your angina worsening.

If you forget to take it

If it is almost time for your next dose, skip the dose you missed and take your next dose when you are meant to. Otherwise, take it as soon as you remember and then go back to taking it as you would normally.

Do not take a double dose to make up for the dose that you missed. This may increase the chance of you getting an unwanted side effect.

If you are not sure what to do, ask your doctor or pharmacist. If you have trouble remembering when to take your medicine, ask your pharmacist for some hints.

If you take too much (overdose)

Immediately telephone your doctor or Poisons Information Centre (telephone 13 11 26), or go to the Accident & Emergency department at your nearest hospital, if you think you or anyone else may have taken too much Diltiazem. Do this even if there are no signs of discomfort or poisoning. You may need urgent medical attention. Keep these telephone numbers handy.

Symptoms of an overdose may include dizziness, a slow or irregular heart beat or pain in the left arm and chest.

While you are taking Dilzem CD capsules

Things you must do

Be sure to keep all of your doctor’s appointments so that your progress can be checked.

If you become pregnant while you are taking Dilzem CD capsules, tell your doctor immediately.

If you plan to have surgery that needs a general anaesthetic, tell your doctor or dentist that you are taking Dilzem CD capsules. Your blood pressure may drop suddenly.

If you are about to be started on any new medicines, tell your doctor or pharmacist that you are taking Dilzem CD capsules.

Tell any other doctors, dentists and pharmacists who are treating you that you are taking Dilzem CD capsules.

Things you must not do

Do not stop taking Dilzem CD capsules, or lower the dosage, without checking with your doctor. If you are taking Dilzem CD capsules for angina, stopping the capsules suddenly may bring on an angina attack. Your doctor may want you to gradually reduce the amount of Dilzem CD capsules you are taking before stopping completely.

Do not give Dilzem CD capsules to anyone else, even if they have the same condition as you.

Do not take Dilzem CD capsules to treat any other complaints unless your doctor tells you to.

Things to be careful of

Be careful driving or operating machinery until you know how Dilzem CD capsules affect you. As with other calcium channel blocker medicines, diltiazem may cause dizziness or lightheadedness in some people. Make sure you know how you react to Dilzem CD capsules before you drive a car, operate machinery, or do anything else that could be dangerous if you are dizzy or lightheaded.

Side Effects

Tell your doctor or pharmacist as soon as possible if you do not feel well while you are taking Dilzem CD capsules.

Dilzem CD capsules help most people with angina or high blood pressure, but it may have unwanted side effects in a few people. If you are over 65 years of age you may have an increased chance of getting side effects.

All medicines can have side effects. 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 or pharmacist to answer any questions you may have.

Tell your doctor if you notice any of the following and they worry you:

  • swelling of the ankles or fingers
  • flushing
  • headache
  • nausea
  • lightheadedness
  • weakness or tiredness

These side effects are usually mild.

Tell your doctor immediately, or go to Accident & Emergency at your nearest hospital if you notice any of the following:

  • you feel continuously dizzy or light headed
  • your heart beats irregularly, slowly, or very quickly
  • rash or hives
  • pain, which may be severe, in your left arm and chest
  • shortness of breath, sometimes with tiredness, weakness and reduced ability to exercise, which may occur together with swelling of the feet or legs, due to fluid build up

These may be serious side effects. You may need medical attention. Serious side effects are rare.

Do not be alarmed by this list of possible side effects.

You may not experience any of them.

After taking Dilzem CD capsules


Keep your medicine in the pack until it is time to take it. If you take your medicine out of the pack, it may not keep well.

Keep the medicine in a cool dry place where the temperature stays below 25°C.

Do not store any medicines in the bathroom or near a sink. Do not leave them in the car or on windowsills. Heat and dampness can destroy some medicines.

Keep your medicines where children cannot reach them. A locked cupboard at least one-and-a-half metres above the ground is a good place to store medicines.


If your doctor tells you to stop taking your Dilzem CD capsules, or the expiry date has passed, ask your pharmacist what to do with any that are left over.

Product description

What it looks like

Dilzem CD capsules 180mg are light turquoise blue and light blue opaque capsules. “APO 180” is printed on them in white ink.

Each pack of Dilzem CD capsules 180mg contains 30 capsules. (AUST R 91870)

Dilzem CD capsules 240mg are light blue capsules. “APO 240” is printed on them in white ink.

Each pack of Dilzem CD capsules 240mg contains 30 capsules. (AUST R 91871)


Dilzem CD capsules contain:

Active ingredients:

  • Diltiazem hydrochloride 180mg or 240mg

Other ingredients:

  • methylcellulose
  • microcrystalline cellulose
  • tributyl citrate
  • polysorbate 80
  • talc
  • eudragit
  • methacrylic acid copolymer
  • gelatin
  • Brilliant blue FCF CI42090
  • titanium dioxide

Dilzem CD capsules do not contain lactose, sucrose, gluten or tartrazine.


Douglas Pharmaceuticals Australia Ltd ABN 17 003 854 626 Unit 3/10 Inglewood Place Norwest Business Park Baulkham Hills, New South Wales Australia 2153

Date of leaflet preparation: 31 July 2002

Published by MIMS May 2003