Download What are ototoxic drugs?

Drugs and hearing
loss
Drugs and hearing loss
This factsheet is part of our Ears and ear problems range. It is written for people who
would like to find out more about ototoxic drugs – these are drugs that can occasionally
cause hearing loss.
Read this factsheet to find out:
 What are ototoxic drugs?
 How might ototoxic drugs cause hearing loss, balance problems and tinnitus?
 Should I change my medication?
 What is being done to make ototoxic drugs safer?
 What about aspirin?
 What about antibiotics?
 What about drugs used for treating cancer?
 What about diuretics?
 What about antimalarial drugs?
 Where can I get further information?
If you would like this factsheet on audio tape, in Braille or in large print, please contact our
helpline – see front page for contact details.
Medical disclaimer
You should not change the dose of any medication you are taking, or stop taking it, as a
result of reading this factsheet, unless the doctor who prescribed the medication agrees it
is safe to do so. If you have any questions about any medication you are taking, or are
about to take, speak to your GP or pharmacist.
What are ototoxic drugs?
The word ‘ototoxic’ derives from the Greek terms for ear and poisonous. Ototoxic drugs
may cause damage to the inner ear, resulting in hearing loss, balance problems and
tinnitus.
Tinnitus is the medical term to describe noises that people can hear in one ear, both ears
or in the head, such as ringing, buzzing or whistling. The sounds can vary from person to
person, but the common link is that they do not have an external source. See our tinnitus
factsheets and leaflets for more information.
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Over 100 classes of drug have been associated with ototoxicity. However, they are not
usually given as a medicine that you need to take regularly. Many of the drugs described
here are only ototoxic if taken in a large or excess dose. However, some are used in
situations to try to save life.
How might ototoxic drugs cause hearing loss, balance problems
and tinnitus?
Hearing loss
Ototoxic drugs damage the following areas:

The structures of the inner ear, like the hair cells, and/ or

The auditory nerve, which carries sound information to the brain.
Hearing loss caused by problems with the sensory cells or the hearing nerve in the inner
ear is known as sensorineural hearing loss. Sensorineural hearing loss is usually
permanent. Other drugs can cause temporary hearing loss. For an explanation of how the
ear works, see our leaflet about how to take care of your ears.
Balance problems
Sometimes, ototoxic drugs can damage the balance system in the inner ear, leading to
dizziness and/or balance problems. For more information, see our factsheet Dizziness
and balance problems.
Tinnitus
Tinnitus can be a side effect of ototoxic drugs. It is often the first sign that your hearing
may be damaged.
Should I change my medication?
If you think that a drug you are taking is causing hearing loss or making your existing
hearing loss worse, you should discuss this with your doctor before you decide to reduce
the dose or stop taking the medication altogether.
If you are convinced that a particular drug is causing your hearing loss, your doctor may be
able to prescribe another drug that does not affect your hearing in the same way. There is
usually more than one drug available to treat most conditions. If this is not possible in your
case, you will have to decide whether the benefits of taking the drug outweigh the
possibility of permanently damaging your hearing.
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You should only come off a drug if you have talked about it with your doctor first. You
should go back to your doctor if you have withdrawal symptoms. You may be able to take
the drug at a lower dose for a while, and then reduce the dose gradually.
What is being done to make ototoxic drugs safer?
We are funding research into how ototoxic drugs can cause hearing loss and how to
prevent them doing so. For more information about progress in this area, see the
biomedical research section of our website.
What about aspirin?
Aspirin is a drug taken to:

treat colds, period pain, headaches and joint or muscular aches

reduce fever

help the symptoms of arthritis

help prevent blood clots from forming.
What are the side effects of aspirin?
When taken in its correct dose, aspirin is very unlikely to cause side effects. If taken in a
large dose or an overdose, aspirin sometimes causes the following side effects:

tinnitus

nausea

digestive problems

dizziness

sweating.
These side effects are usually temporary and should disappear if you stop taking aspirin.
For more information about tinnitus and aspirin, read our factsheet Drugs, stress and
tinnitus.
Can aspirin cause hearing loss?
There is little evidence that aspirin causes permanent hearing loss. If your doctor has
prescribed aspirin for you, you can always discuss changing the dose before you go
ahead.
What about antibiotics?
Antibiotics are a group of drugs that treat bacterial infections, ranging from quite mild
infections to serious, life-threatening diseases.
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Which antibiotics cause hearing loss?
The group of antibiotics that are most likely to cause hearing loss are aminoglycosides.
These include:
 gentamycin
 streptomycin
 neomycin.
These antibiotics are often used to treat serious or life-threatening bacterial infections such
as tuberculosis (TB). They are sometimes prescribed when a bacterial infection does not
improve after treatment with antibiotics that are not in the aminoglycosides group.
What are the risks of using drugs from the aminoglycosides group?
The risk of hearing loss from aminoglycosides can increase, depending on:

how high your dose is

how long you take it for

whether you are given it by injection.
If you are prescribed aminoglycosides, you should be aware of the risk of permanent
damage to your hearing. The effects are usually monitored when you are in hospital by
regular blood tests to estimate how much of the drug is in your bloodstream.
Aminoglycosides are generally prescribed to treat serious, life-threatening diseases, where
saving your life is judged more important than the possible risk of damaging your hearing.
What about drugs used to treat cancer (cytotoxic drugs)?
Cytotoxic drugs are a group of drugs that destroy cells or prevent their regrowth. These
drugs are mainly used to treat cancer, through chemotherapy. Cytotoxic drugs attack
healthy cells as well as cancerous ones, so they can cause a variety of side effects.
Can cytotoxic drugs cause hearing loss?
A group of cytotoxic drugs can cause hearing loss. These include:
 Carboplatin – mainly used to treat ovarian cancer and lung cancer.
 Cisplatin – mainly used to treat ovarian, testicular, lung or bladder cancer.
 Oxaliplatin – mainly used to treat bowel cancer.
It is thought that carboplatin is less ototoxic than cisplatin, although all these drugs can
cause permanent damage to hearing.
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Cytotoxic drugs are often used in combination with other drugs, which can affect the
severity of hearing loss, depending on which drugs are used together. If you are
prescribed cytotoxic drugs, the effects will be carefully monitored. Tell your doctor
immediately if you are taking these drugs and you:
 Develop tinnitus.
 Start to feel unsteady.
 Have difficulty hearing.
These signs can be the first indication of hearing loss as a result of taking ototoxic drugs.
What about diuretics?
Diuretics are a large class of drugs that increase the amount of urine produced by the
kidneys. Diuretics are used to treat conditions in which fluid builds up in the tissues. These
include heart and kidney failure and some liver diseases. Diuretics may also be used to
treat high blood pressure.
Which diuretics can cause hearing loss?
Of the commonly used diuretics, only loop diuretics are known to cause hearing loss. They
are called loop diuretics because they work in the region of the kidney known as the loop
of Henle. Loop diuretics are commonly used to treat a build-up of fluid – for example, if you
have a heart attack. Examples of loop diuretics are furosemide (also known as frusemide),
torasemide and bumetanide.
Loop diuretics are usually taken by mouth, but you may be given them by injection. Loop
diuretics are usually only ototoxic when they are given in large doses by injection in lifethreatening situations. If you already have hearing loss and balance problems, you should
tell your doctor, as it would be better for you to receive treatment with diuretics that do not
have ototoxic side effects.
What about antimalarial drugs?
Malaria is a parasitic disease spread by the bites of infected mosquitoes. Antimalarial
drugs should be taken before, during and after a visit to an area where malaria is common.
They can also be taken as treatment for malaria. There are many types of antimalarial
drugs available, which have different side effects. Some common side effects of
antimalarial drugs include tinnitus, headaches, nausea, dizziness, sleep disorders, anxiety
and depression.
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For more about the relation between antimalarial drugs and tinnitus, read our factsheet
Drugs, stress and tinnitus.
Can antimalarial drugs cause hearing loss?
In rare cases antimalarial drugs such as chloroquine and quinine, can cause hearing loss,
although there isn’t currently enough evidence around this. Chloroquine is one of the
oldest antimalarial medicines and many strains of malaria are now resistant to it.
The risks of any side effect from antimalarial drugs may be greater if you actually get
malaria and are given high doses to treat the disease. Patient information leaflets warn
against hearing loss if you take an overdose of the medication. Risks of side effects are
lower when you take lower doses to stop you from getting malaria in the first place.
If you are about to travel to an area where malaria is common and are concerned about
the possible side effects of antimalarial drugs, you should discuss this with your doctor.
You should balance the risks of the side effects against the chance of getting malaria.
Where can I get further information?
Our helpline offers a wide range of information on many aspects of hearing loss. You can
contact us for further copies of this factsheet and our full range of factsheets and leaflets –
see the cover page for contact details.
Action on Hearing Loss Information, May 2012
The Royal National Institute for Deaf People. Registered Office: 19-23 Featherstone Street, London EC1Y 8SL.
A company limited by guarantee registered in England and Wales No. 454169, Registered Charity Numbers 207720 (England and
Wales) and SC038926 (Scotland).
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