drug-medicine : adalat retard

PATIENT INFORMATION LEAFLET

PLEASE READ THIS LEAFLET CAREFULLY BEFORE TAKING ADALAT RETARD

Adalat® retard

"What exactly is high blood pressure?"

Blood has to be pumped to all the organs in your body and this is done by the heart. As the blood is pumped around the body, it pushes against the walls of your blood vessels creating pressure. This is your "blood pressure". There are upper and lower limits of blood pressure which are generally accepted as normal. Your blood pressure can be greater than the upper limit and not cause you any discomfort. The medical term for this is hypertension.

Although high blood pressure may not make you feel ill, it can in the long-term put a strain on your heart because of the extra pumping effort it causes and may lead to other problems such as heart disease or a stroke.

"What exactly is angina?"

"Angina" is a pain usually experienced by patients who are suffering from coronary artery disease. In this disease the arteries supplying blood to the heart become stiffer and partially blocked. This results in less blood getting to the muscle which makes up the largest part of the heart. The heart is a muscular pump which circulates the blood throughout the whole body. It needs oxygen to do this and this is supplied by the blood. If the arteries which supply the muscle of the heart cannot deliver enough oxygen for the heart muscle to work properly, then pain is experienced. This pain is known as angina. Usually, angina occurs upon physical exercise and the pain will stop when the exercise stops. Sometimes, however, it can occur at rest.

Treating angina will reduce the frequency of your anginal attacks. Most medicines which successfully treat angina either improve the blood flow to the heart muscle or reduce the speed of the beating heart. Either effect may reduce the likelihood of long-term damage to the heart.

ADALAT RETARD

(nifedipine)

What do my tablets contain?

Each grey-pink, circular tablet contains 20 mg of the active ingredient nifedipine and is marked "1U" on one side with the Bayer symbol on the other side.

Adalat retard tablets also contain microcrystalline cellulose, polysorbate 80, hypromellose, lactose, maize starch, macrogol, and magnesium stearate. Titanium dioxide (E171) and iron oxide (E172) are included as colouring agents.

Your medicine comes in packs of 56 tablets.

The active ingredient, nifedipine, is one of a group of medicines called calcium antagonists. These relax and expand blood vessels.

Why have I been prescribed Adalat retard by my doctor?

It has been prescribed by your doctor to treat your high blood pressure or to reduce the frequency of your anginal attacks.

In high blood pressure, nifedipine works by widening the blood vessels. This creates less resistance to the blood flow, and results in lower blood pressure, which in turn reduces the strain on your heart. A good comparison is to imagine the difference in pressure you feel when you blow hard through a straw compared with something larger like the cardboard tube in a kitchen roll. You will feel less pressure with the cardboard tube because the hole is larger. It creates less resistance in the same way as does a widened blood vessel.

In angina, nifedipine works by opening up the arteries supplying the heart muscle and this allows more blood and oxygen to reach the muscle, decreasing the chances of angina occurring when extra strain is placed upon the heart.

When should I not take Adalat retard?

Do not take Adalat retard if you have previously had an allergic reaction to the active ingredient nifedipine or to any other similar drugs (known as dihydropyridines). If you are unsure about this, ask your doctor.

Do not take this medicine if you are pregnant or breast-feeding. If you are taking it and think that you may be pregnant or are planning a family, consult your doctor.

Do not take this medicine if you are taking the antibiotic, rifampicin.

If you have been told that you have a narrowing (stenosis) of the aortic valve of the heart, you should not take this medicine.

Do not take this medicine if you have experienced a collapse which was caused by a heart problem (cardiogenic shock), during which you would have become breathless, pale and had a cold sweat and dry mouth.

If the severity or frequency of your angina has rapidly worsened over a matter of hours or days, you must contact a doctor. You may be advised not to take Adalat retard.

Adalat retard should not be used for the treatment of a heart attack or within one month of a heart attack.

You should not take Adalat retard to treat an angina attack when it occurs, but rather to reduce the frequency of the angina you experience over time.

You should not take this medicine if your blood pressure is continuing to rise despite treatment.

This is a condition known as malignant hypertension.

If you are unsure whether you might have any of these conditions, please ask your doctor.

What special precautions should I take?

You should not start taking Adalat retard within three days of drinking grapefruit juice. If you have, speak to your doctor. In addition, you should not drink grapefruit juice whilst taking Adalat retard. This is because grapefruit juice is known to increase the blood levels of the active ingredient, nifedipine. This effect can last for at least three days after the last ingestion of grapefruit juice.

If you are allergic to any of the other ingredients of this medicine, please tell your doctor before starting your course of treatment.

If you experience chest pains within 1 - 4 hours of taking your FIRST dose of Adalat retard, contact your doctor BEFORE YOU TAKE THE NEXT DOSE. He/she may wish to change your treatment.

Remind your doctor if you suffer from low blood pressure and he/she prescribes Adalat retard for your angina.

If you have a heart condition where your heart cannot cope with increased strain (poor cardiac reserve), you should tell your doctor.

If you notice increased breathlessness or swelling of the ankles, or if your heart condition gets worse whilst taking your medicine, you should contact your doctor.

If you are a diabetic, the treatment for your diabetes may need to be adjusted. If you have any questions about this, ask your doctor.

Patients who are receiving kidney dialysis and have a very high blood pressure and low blood volume might experience a sudden drop in their blood pressure when they take Adalat retard. If you are on kidney dialysis please consult your doctor before taking this medicine.

Your doctor may, under certain conditions, think it necessary to keep you on Adalat retard whilst you are pregnant. If this is the case particular care should be exercised if you are also having magnesium sulphate injections.

Drugs like Adalat retard have been shown in laboratory experiments to impair sperm function. If you are male and have been unsuccessful in fathering a child by in vitro fertilisation please consult your doctor.

Adalat retard may interfere with the results of certain urine tests. If you have given a urine sample, inform the person responsible that you are taking this medicine.

Before taking Adalat retard, tell your doctor if you are taking any other medicines, whether bought or prescribed, since some medicines can interfere with your treatment. In particular, tell your doctor if you are taking:

other drugs to treat high blood pressure
cimetidine, to treat stomach ulcers
the medicines digoxin, diltiazem, quinidine or beta-blockers, which are used to treat heart conditions
the antibiotics rifampicin and combination treatment quinupristin/dalfopristin
the anti-epileptic drug phenytoin
cisapride, a drug used to treat reduced movements of the gullet and stomach.

The effect of the following drugs on Adalat retard is uncertain. Therefore, as an additional precaution, please tell your doctor if you are taking:

the antibiotics erythromycin, ketoconazole, itraconazole or fluconazole
the HIV protease inhibitors indinavir, nelfinavir, ritonavir, saquinavir or amprenavir
the antidepressant drugs fluoxetine and nefazodone
tacrolimus, an immunosuppressant used to prevent the rejection of transplant organs
carbamazepine and valproic acid, which are both used for the treatment of epilepsy
the barbiturate phenobarbitone, used primarily to treat insomnia and anxiety

The following drugs do not interact with Adalat retard: ajmaline, aspirin, benazepril, candesartan cilexetil, debrisoquine, doxazosin, irbesartan, omeprazole, orlistat, pantoprazole, ranitidine, rosiglitazone, talinolol and triamterene hydrochlorothiazide.

It is possible that you may react to Adalat retard. Reactions can vary in intensity from individual to individual and may impair your ability to drive or operate machinery. This applies particularly at the start of treatment, on changing the medication and in combination with alcohol.

When and how do I take Adalat retard?

Take the tablets as prescribed by your doctor. Usually this will be one tablet taken every 12 hours, but your doctor may decrease or increase this dose depending on how well your blood pressure or angina is being controlled. The maximum dose you should take is two tablets (40 mg) every 12 hours. The tablets should be swallowed with a little water. You should not take your tablet(s) with grapefruit juice.

If you suffer from a liver disorder, your doctor may want to start your treatment on a low dose and increase it with careful monitoring of your blood pressure or angina. If so, he/she will prescribe a tablet for you containing 10 mg of nifedipine called Adalat retard 10. You should start your therapy with one Adalat retard 10 tablet every 12 hours.

It is possible that you may have to take these tablets indefinitely. You may want to discuss this with your doctor.

If you are elderly, lower doses of this medicine may be prescribed by your doctor.

This medicine is not recommended for use in children.

DO NOT EXCEED THE PRESCRIBED DOSE

Exceeding the correct dosage or taking an overdose may cause your blood pressure to become too low and your heart beats to become irregular. Also, it may lead to dizziness, confusion, low blood oxygen levels and possibly unconsciousness.

If you take more than the prescribed dose, or in the event of an overdose, seek medical advice immediately and, if possible, take your tablets or the box with you to show the doctor.

What should I do if I forget to take my Adalat retard?

You should take your normal dose immediately and then continue taking your tablets as prescribed, waiting 12 hours before taking your next dose.

What side-effects may I experience?

As with all medicines, Adalat retard can occasionally cause side-effects in some people. The most commonly reported (less than 1 person in 10) are: headache, general swelling and swelling of the ankles and legs, flushing, feeling sick (nausea), dizziness, weakness or loss of strength and energy, and an irregular heartbeat (palpitations).

Other less commonly reported side-effects (in less than 1 person in 100) are: general pain, abdominal and chest pain, general feeling of being unwell, low blood pressure when rising to the standing position, fainting, a fast heart beat (tachycardia), constipation, diarrhoea, dry mouth, indigestion, vomiting, pain in the joints and muscles, nervousness, pins and needles, trembling, vertigo, sleeping disorders, difficulty in breathing, skin reactions such as a rash, itching or sweating, an increase in the need to pass water and bed wetting.

As with similar drugs which act on blood vessels, anginal pain may occur at the start of treatment with Adalat retard.

Because of the nature of coronary artery disease, heart attacks have occurred in patients treated with the active ingredient, nifedipine. It has not been shown that these heart attacks were due to treatment with nifedipine.

The following rare side-effects have been reported (in less than 1 person in 1000): enlarged abdomen, allergic reactions which may appear as a yellowing of the skin (jaundice), blistering of the skin when exposed to sunlight, low blood pressure, flatulence (wind), problems with your digestive system, increased gamma glutamyl-transpeptidase (an enzyme that occurs naturally in the body), increased sensitivity particularly of the skin, hives, mood changes, problems with your eyes and a failure to achieve or maintain an erection (impotence). Increases in liver proteins (enzymes) may also occur rarely.

A number of very rare side-effects have also occurred in approximately 1 person in 10,000: a decrease in the number of blood cells, a burning sensation of the skin and an allergic reaction that may become severe. There have also been reports of tender or swollen gums that may bleed and a slight development of breast tissue in older men.

All of the symptoms above usually go away when treatment with Adalat retard is stopped.

IF YOU EXPERIENCE ANY OF THESE EFFECTS OR ANY OTHER SIDE EFFECTS, TELL YOUR DOCTOR IMMEDIATELY. YOUR DOCTOR WILL GIVE YOU ADVICE.

How should I store my Adalat retard tablets?

Store in the original container. The tablets should be protected from strong light, so only remove the tablet from the box or blister strip when you are about to take it.

KEEP ALL MEDICINES OUT OF THE REACH AND SIGHT OF CHILDREN

Do not use tablets after the expiry date which is marked on both the outer carton and on each blister strip of tablets.

If you find that you have tablets after their expiry date, return them to your local pharmacist (chemist) who will dispose of them properly.

Medicine: adalat retard