Thinking clearly about your medicines: managing side effects

Medicines can bring many benefits but they can also have side effects that are not intended or desired. Side effects can occur when taking a single medicine or because a number of medicines are taken at the same time. As we get older we can become more sensitive to medicines. This may result in more side effects. This topic is about anticholinergic (an-tee-kol-in-er-jik) side effects which may occur with many commonly used medicines.

Problems that you might think are normal with ageing such as forgetfulness, confusion and difficulty concentrating can sometimes be caused by the anticholinergic side effects of one or more of your medicines. Medicines used to treat a variety of conditions including airways disease, bladder problems and allergies, can cause anticholinergic side effects.

These side effects can be found in many medicines – complementary, herbal, those prescribed by your doctor or those purchased without a prescription.

Always talk to your doctor if you are concerned about your medicines.

Which medicines can cause anticholinergic side effects?

Many medicines can cause anticholinergic side effects, even some eye drops. Medicines with anticholinergic side effects are used to treat many conditions including:

  • allergies
  • respiratory conditions such as airways disease
  • coughs and colds
  • bladder control problems
  • stomach problems including motion sickness
  • insomnia and sleeping problems
  • depression and anxiety
  • neuropathic (nerve) pain.

Talk to your doctor or other health professional about all the medicines you are taking and ask about those which can cause anticholinergic side effects. Your doctor may consider other options.

What anticholinergic side effects should I look out for?

All medicines have possible side effects when used alone, or with other medicines. You are more likely to experience side effects when you start a new medicine, increase the dose, or add another medicine. Everyone responds to a medicine or combination of medicines differently. Possible anticholinergic side effects are shown in Figure 1.

As we age we tend to have more health issues and may require additional medicines. However our bodies can become more sensitive to medicines, even those we have been taking for some time, and our ability to tolerate them may lessen.

Be aware of any changes or new symptoms that you experience, even if you are unsure if they are related to your medicines. Talk to your doctor about any unwanted side effects you may be experiencing.

Figure 1.

What should I do if I am concerned about my medicines?

Ask your doctor which of your medicines can cause anticholinergic side effects and if you may be experiencing some of these unwanted effects. Sometimes just adding one more medicine can tip the balance. Be guided by your GP who may be able to recommend a different medicine, reduce the dose, or offer a non-medicine alternative.

The more medicines you take, the more difficult it can be to remember important information about them. Keeping an up-to-date list of all your medicines, including those you buy over the counter, can help your doctor assess the cumulative effect of your medicines.

Your doctor or pharmacist can help you prepare your list with the name of each medicine, dose, directions, storage and possible side effects. It is a good idea to take a copy with you whenever you visit a health professional. Print out the NPS MedicineWise medicines list or download the free smartphone app. See:

Ask your doctor about a regular review of your medicines. Having a medicines review can help you better understand your medicines and how to take them safely with good outcomes.

Your pharmacist can visit you to review your medicines, including those that can cause anticholinergic side effects. You may like to have a family member or carer with you. Tell your doctor and pharmacist about all your medicines, including those you may have bought from the pharmacy, health food shop or supermarket.

Talk to your doctor before starting, changing or stopping a medicine, including complementary or herbal medicines.

What should I ask my doctor?

Your treatment is about you as an individual, not just about your medicines. You know your own health problems, needs and preferences better than anyone else. Ask your GP about all your options so that together you can make an informed decision about what is best for you.

You play an important role in your health and wellbeing by understanding your medicines and being comfortable talking about them. Ask your doctor about all your choices and about the benefits and harms of each of these options. Finding the right balance can lessen the burden of unwanted side effects and contribute to a better quality of life.

Ask these questions:
  • Do any of my medicines (including over the counter or herbal medicines) cause anticholinergic side effects?
  • Will I be taking my medicines for the long term or short term?
  • Are there non-medicine options available?
  • Should I continue all my current medicines?
  • Should I replace, reduce or stop any of my medicines?
  • Could any of my medicines be contributing to unwanted symptoms?

Return to top