Cyclopenthiazide tablets

Cyclopenthiazide is a diuretic (a water tablet).

It is best taken in the morning.

Any side-effects are usually mild, but may include feeling sick or dizzy.

About cyclopenthiazide

Type of medicine Thiazide diuretic
Used for High blood pressure, fluid retention, and heart failure
Also called Navidrex®; Navispare® (cyclopenthiazide with amiloride)
Available as Tablets

Cyclopenthiazide belongs to a group of medicines called thiazide diuretics. A diuretic is a medicine which increases the amount of urine that you pass out from your kidneys. They are often referred to as water tablets. Diuretics are a common treatment for hypertension (high blood pressure). They are also used to clear excess fluid from your body in conditions where your body retains more than it needs. This is called oedema. Cyclopenthiazide is also useful in people who have heart failure. This is a condition where your heart is not functioning as well as it should.

Diuretics like cyclopenthiazide work by interfering with the transport of salt and water across certain cells in your kidneys. The effect of this is to make your kidneys pass out more urine. This removal of fluid reduces your blood pressure and helps reduce the work your heart has to do.

Cyclopenthiazide may also be given alongside other diuretics. When it is used like this, you may be prescribed a combination tablet, such as Navispare®. This brand contains cyclopenthiazide with amiloride. Combination tablets like this help to reduce the number of tablets you need to take each day.

Before taking cyclopenthiazide

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking cyclopenthiazide it is important that your doctor or pharmacist knows:

  • If you are pregnant or breast-feeding.
  • If you have kidney or liver problems.
  • If you have gout, diabetes, or systemic lupus erythematosus (an inflammatory condition also called lupus or SLE). These conditions may be made worse by diuretics.
  • If you have been told by a doctor that you have low sodium or potassium levels in your blood, or high calcium levels in your blood.
  • If you have a problem with your adrenal glands, called Addison's disease.
  • If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
  • If you have ever had an allergic reaction to a medicine.

How to take cyclopenthiazide

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The leaflet will give you more information about cyclopenthiazide and a full list of side-effects which you may experience from taking it.
  • Take cyclopenthiazide exactly as your doctor has told you. The usual dose is ½-1 tablet daily. Your doctor is likely to recommend that you take your dose in the morning. This is so it works during the day and your sleep is not disturbed by you needing to get up to go to the toilet during the night.
  • You can take the tablets before or after your meals.
  • If you forget to take a dose, take it as soon as you remember. However, if it is after 6 pm in the evening, you should skip the forgotten dose and continue as usual the next day. Do not take two doses together to make up for a missed dose.

Getting the most from your treatment

  • Diuretics like cyclopenthiazide help you to lose water. Occasionally you may lose too much and become dehydrated. Let your doctor know if you feel constantly thirsty, your mouth is dry, or your skin looks and feels dry.
  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. The salt balance in your bloodstream may be upset by cyclopenthiazide and your doctor may want you to have a blood test from time to time to check for this.
  • If you have been prescribed cyclopenthiazide for high blood pressure, your treatment is likely to be long-term. Although many people with high blood pressure do not feel unwell, if left untreated, high blood pressure can harm your heart and damage your blood vessels. This damage may later result in a heart attack, stroke, or kidney problems, so it is important that you continue to take these tablets regularly to help reduce the risk of this. You may also be given some lifestyle or dietary advice by your doctor, such as stopping smoking, reducing the amount of salt in your diet and taking some regular exercise. Following this advice will also help to reduce the risk of damage to your heart and blood vessels.
  • Drinking alcohol while you are on cyclopenthiazide may make you feel dizzy. Ask for your doctor's advice about whether you should avoid alcohol.
  • If you buy any medicines, check with a pharmacist that they are suitable to take alongside cyclopenthiazide.
  • If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.
  • If you have diabetes, cyclopenthiazide may affect your blood sugar levels. Test your blood or urine regularly and speak with your doctor if you notice any significant changes.

Can cyclopenthiazide cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Common cyclopenthiazide side-effects
What can I do if I experience this?
Feeling sick, stomach upset This is usually mild, but it may help to take cyclopenthiazide after food
Feeling dizzy, particularly when you stand up (due to low blood pressure) Getting up and moving more slowly should help. If you begin to feel dizzy, lie down so that you do not faint, then sit for a few minutes before you try standing up again

How to store cyclopenthiazide

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.