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Using over the counter medicines if you have renal failure or are on dialysis

Patient information A-Z

What are over the counter (OTC) medicines?

Over the counter medicines are medicines that you can buy without a prescription from pharmacies, supermarkets or garages to treat minor ailments.

As a patient with a renal condition there are sometimes problems with taking medicines that you can buy over the counter and this is important whether you have poor renal function or if you are on dialysis.

Examples of over the counter medicines include:

  • Paracetamol (such as Panadol® )
  • Ibuprofen (Such as Nurofen® )
  • Cough mixtures (such as Benylin® )
  • Cold remedies (Such as Lemsip® )

Problems that may happen with medicines that you can buy over the counter

They may cause problems with other medicines you take.

  • Some may make your kidney function worse.
  • Some products contain things that should be avoided if you have renal failure or if you are on dialysis such as potassium, sodium or aluminium.

However, if you talk to your doctor or pharmacist, it should still be possible for you to buy suitable medicines to treat minor ailments.

What OTC medicines can I take and which should I avoid if I have poor renal function or if I am on dialysis?

You may have a number of medical conditions and are therefore prescribed several medicines from your doctor. As a result, some of the medicines that can be bought over the counter from pharmacies and other shops may be unsuitable for you.

Aspirin and ibuprofen belong to a group of medicines called Non Steroidal AntiInflammatory Drugs (NSAIDs). NSAIDs can be very harmful to kidneys, so if you have poor renal function or are on dialysis all NSAIDs should be avoided unless taken on the advice of your doctor.

Always let the pharmacist know that you have poor renal function or if you are on dialysis before you buy any medicine over the counter. Don’t take any medicines which have not been prescribed for you without checking with a pharmacist first.

The table below summarises some the of the medicines people commonly buy over the counter and tells you which you can buy and use and which you should avoid.

Ailment What to avoid Suitable
Additional comments
Headache What to avoid Ibuprofen
All effervescent products
Additional comments See your doctor if
symptoms don't
improve. Aspirin
prescribed by your
doctor at a low dose
for the heart is safe
to take - but only if it
is advised by your
Colds and coughs What to avoid Any medicines containing a decongestant - especially if you take tablets for high blood pressure.
Paracetamol for aches and pains
Try simple linctus to soothe coughs and sore throats - ask for sugar free products if you are diabetic.
Additional comments Try a menthol or steam inhalation to clear any congestion.
Muscle aches What to avoid Tablets or creams containing ibuprofen or similar medicines such as ketoprofen. Suitable
Deep Heat® or Ralgex®
Additional comments None
Indigestion What to avoid Some people should avoid any preparations containing aluminium, sodium, potassium or magnesium for example products such as Gaviscon® or Rennies® Suitable
Preparations containing calcium (unless you have been told your calcium is high).
Additional comments See your doctor if you have indigestion regularly.
Constipation What to avoid Fybogel® (ispaghula husk) if you have a restricted fluid intake. Suitable
Additional comments See your doctor if no
better in a week.
Diarrhoea What to avoid Rehydration salts unless recommended by your doctor. Suitable
Additional comments If severe, contact your doctor.
Vitamins What to avoid Vitamin A
Vitamin D
Fish oil supplements (including cod liver oil)
Not necessary unless prescribed by your
Additional comments -

Some points to remember when buying medicines

  • It is very important to tell any doctor or pharmacist recommending a medicine for you about your renal condition and the medicines you are taking.
  • You should only treat minor ailments by yourself for a few days. If your symptoms change, get worse or last for more than a couple of days, see your doctor.
  • Be aware that some of the tablets your doctor gives you can also be bought over the counter. Be careful not to take double the dose.
  • Remember to tell the pharmacist that you have poor renal function or that you are on dialysis and also if you are diabetic or have had an allergic reaction to any medicine.
  • Try to use the same pharmacy so that the pharmacist can build up a complete picture of all the drugs you are taking. They will then be able to provide you with the best advice.
  • If you find that you need to treat the same symptoms frequently, please do not forget to mention them to your doctor at your next visit.
  • Be careful not to take more than one preparation with paracetamol in - do not forget that co-codamol and co-dydramol contain paracetamol.
  • Effervescent tablets are best avoided because they contain sodium and potassium.
  • You should remember that, although some medicines are not recommended for you to buy, they may be safe for your doctor to prescribe them.

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