At first you may be prescribed only low doses of Parkinson's medication. Or your doctor may suggest you delay taking medication until symptoms increase. This is because medicines may become less effective over time, or cause side effects. Over time as Parkinson’s progresses, your symptoms will change. Your specialist may gradually increase the dose and add new medications to control symptoms as effectively as possible.

Your doctor or Parkinson’s nurse will advise the times of day you should take the medication so that it works best for you.

Important! It is very important to keep to the daily dose prescribed by your doctor and follow any instructions you are given. Following your medication regime carefully is a key part of effectively managing your Parkinson’s. Work closely with your doctor to agree your treatment regime, so that you are comfortable with what you need to take, when and how.

If you do not take the right dose of medication at the right time, it could mean that your symptoms are not well controlled. This could not only impact on your quality of life but it could also increase the need for further treatment. It could also waste public money spent on healthcare.

Remember that a healthy lifestyle will also help to manage your symptoms. Eating a balanced diet, taking regular exercise and reducing stress can all help to control symptoms and improve quality of life, as can reducing your alcohol intake and stopping smoking. Remember too that being constipated can affect the way your medication works so talk to your healthcare team if you experience constipation.

For further information on monitoring your response to medication and its timing, see Keeping a Diary.

Specific Parkinson’s medication is almost always the main treatment for the motor (movement) symptoms of the condition. Our movements are regulated by nerve cells in the brain that relay messages using chemicals called neurotransmitters. In people with Parkinson’s, levels of the neurotransmitter dopamine are reduced as the nerve cells (neurons) which produce it gradually die. This results in low levels of dopamine in the part of the brain that controls movement and balance. When nerve cells do not pass on brain messages properly, movement is no longer controlled smoothly and the motor symptoms of Parkinson’s, such as tremor, slowness or muscle stiffness, appear.

Parkinson’s medications manage motor symptoms in one of three ways:

• replacing dopamine in the brain
• stimulating the areas of the brain where dopamine is active
• preventing enzymes from breaking down dopamine in the brain.

The symptoms of Parkinson’s vary from person to person. They may also vary from day to day, hour to hour, even minute to minute. Your own, individual pattern of symptoms will determine what medications you need. It is important to work closely with your doctor to establish a medication regime that suits you. Finding the best medicine, dose and timing may take some time. Because your symptoms will change over time, your medication will sometimes have to change, too.

People with Parkinson’s may also develop non-motor symptoms (not related to movement), such as thinking problems, pain or depression. These are treated with the standard medicines that would be given to a person without Parkinson’s. These medications are not covered in this section as they are not specific to Parkinson’s.

Many people with Parkinson’s take other medicines to treat unrelated conditions. Because some medicines can interact with others, you should always tell your doctor or health professional about any other medicines, remedies or supplements you are taking. This includes over-the-counter medicines that have been bought without a prescription. Even some medicines used to relieve the symptoms of the common cold can affect some Parkinson’s medicines, so it is important to ask your pharmacist which is the best one to take.

Some medicines may have harmful interactions with others – known as contraindications. This can either make existing symptoms worse or bring on new Parkinson’s-type symptoms that will disappear if you stop taking that medicine. If you have any worries or concerns about medication, discuss it with your doctor, Parkinson’s nurse or pharmacist. 

Almost all medicines have possible unwanted side effects that affect some people who take them. Parkinson’s drugs are no exception. The possible side effects of Parkinson’s medicines differ from one drug to another, but may include nausea, vomiting, diarrhoea, dizziness and delirium. Everyone reacts to medication differently, so it is always important to read the leaflet provided that outlines possible side effects.

Some people experience no side effects from Parkinson’s medications. If you do experience side effects or have any concerns, you should discuss these with your doctor, Parkinson’s nurse or pharmacist as soon as possible. You can also report side effects directly using the MHRA Yellow Card Scheme 

Your doctor may prescribe an alternative medication if the one you are using causes side effects. He or she may also prescribe an additional drug to help overcome side effects, for example if levodopa causes nausea.

Some Parkinson’s medications can make you sleepy, perhaps very suddenly. Others can cause a sudden drop in blood pressure when standing (postural hypotension) which can make you feel faint or dizzy. Ask your doctor, Parkinson’s nurse or pharmacist what to do if this happens to you and check it is safe for you to drive.

If your doctor advises you to stop taking a medicine, it may be important to reduce the dose slowly, otherwise you may experience side effects. Sudden withdrawal of medication such as dopamine agonists can cause withdrawal symptoms such as pain or anxiety. Your doctor will advise.

Compulsive behaviour

Many experts believe that certain medications may be linked to compulsive behaviour, for example gambling, hypersexuality, compulsive or binge eating and compulsive shopping. This particularly applies to dopamine agonists such as cabergoline, ropinirole, pramipexole and pergolide. Compulsive behaviour can impact on family and friends as well as you. If you think you may be affected, talk to your doctor straight away so that your medications can be adjusted.

For more information see Compulsive & impulsive behaviour.

Hallucinations and delusions

Hallucinations and delusions can occur as a side effect of some medications. They are particularly associated with dopamine agonists, and with anticholinergics and amantadine, especially in older people. They may occur when medications have been adjusted or if a new one is added. However, hallucinations may occur at any time and may not be related to your medication.

For more information see Hallucinations and delusions.

If you have been taking medication for some time you may notice that its effects wear off before the next dose is due and so symptoms begin to return. This is known as ‘wearing off’ and can affect both movement and non-motor symptoms such as anxiety or feeling low. 

See Wearing off for further information.

If you have been taking medication containing levodopa for some time, you may notice that your motor (movement) symptoms are no longer as well controlled and fluctuate in severity during the day. This is known as ‘motor fluctuations’. You may also find that you develop uncontrollable involuntary movements, called dyskinesia.

See Motor fluctuations for further information.

See Dyskinesia for further information.

It is important to discuss with your doctor what you should do if you forget to take your medication. If this happens you may notice a worsening of your symptoms as the effects of the medicine wear off. Symptoms may either re-emerge or worsen before the next dose is due. ‘Wearing off’ tends to happen more as Parkinson’s progresses. It varies from person to person and there is no standard time frame for when it may occur, or what symptoms you might experience. 

For further information see  Wearing off.

Keeping a diary can be very helpful in monitoring how the symptoms of Parkinson’s affect you and how you respond to your medications. A written record can help to highlight:

• the pattern of symptoms you experience
• the effectiveness of the medications you take and how long they last
• any side effects of medications
• any changes in your emotions or behaviour that may be related to medications

Recording your experiences on a daily basis can also help you effectively communicate to your doctor any changes in your symptoms or response to medication. This can be very useful, particularly as appointments are often too short for doctors to ask lots of questions. Being able to review how you have been over a period of time can help your doctor:

• understand how effective medications are for you personally
• pinpoint any particular difficulties or patterns of symptoms
• decide if your medication needs to be adjusted

If your medication has been changed, keeping a diary will help you and your doctor judge if the change has been effective or if further adjustments are needed.

For more detailed information see Keeping a diary.

• Make sure you understand what each medication is for, how it works and what its effects should be. If you don’t understand something, ask your doctor to explain.
• Know what side effects to look out for. Always check with your doctor, Parkinson’s nurse or pharmacist if you think you may be experiencing unwanted side effects.
• Don’t change the dose, timing or frequency of your medications without first discussing with your doctor or nurse.
• Don’t stop taking a medication suddenly unless your doctor, nurse or pharmacist tells you to. Stopping abruptly can be dangerous so Parkinson’s medications are generally stopped gradually.
• Keep a medication diary to monitor your daily progress and response to medication. A diary will also remind you what you want to discuss at your appointment. As your doctor for a sample medication record.
• Don’t assume that your medication regime will be the same as other people with Parkinson’s – each person’s needs are different and medication is tailored to suit them.
• If you find child-proof bottles or ‘blister’ packs (plastic strips with a foil seal which you ‘pop’ pills out of) difficult to use, ask your pharmacist to provide different types of lids or packaging.
• Ask your pharmacist to use labels with large print if you have trouble reading smaller print.
• Take your medication only as prescribed. Some, but not all, medicines can be taken in a spoonful of yoghurt or fruit purée to make them easier to swallow; some can be crushed or mixed in water. Others may be available in liquid form, or as tablets that dissolve on the tongue. Discuss with your doctor, nurse or pharmacist the best way for you to take your medication.
• Remember that protein in meals can interfere with how medications work. Talk to your doctor if you think this is a problem.
• Decongestants or cold remedies can affect some Parkinson’s medications. Check with your pharmacist which one is safest to use. 

• If you take a number of different medications through the day you may find it helpful to use a pill timer. Resembling an alarm clock, this reminds you when to take the next dose.
• You can also buy various types of tablet organisers that have a compartment for each day, or are split into different sections for each day. Speak to your pharmacist or search on-line.
• If some doses are difficult to remember or at inconvenient times, talk to your doctor or pharmacist to see if timings can be adjusted.

• Keep a record of all the medications you take – both for Parkinson’s and other conditions. Carry it with you in your purse or wallet in case of emergency. Make sure you take this record with you if you go into hospital. If your medication is complicated you could make a chart to track what you take each day.
• Wear a medical alert bracelet or necklace if you want a medical team to know immediately what medications you take in case of an emergency.
• If you stay in hospital make sure staff are aware of the medications you take and the importance of having them on time every time.

Parkinson's Europe's Parkinson's Passport enables you to complete an information booklet about your medications and treatment and then carry it when you are out and about or travelling abroad.

Falsified medicines, also known as Counterfeit medicines, are substandard or fake medicines that fail to meet explicit, scientific specifications. It may be contaminated or contain incorrect ingredients or dose. Such medicines are illegal and can be harmful. According to the World Health Organisation (WHO), counterfeit medicines are often ‘deliberately and fraudulently mislabelled with respect to identity and/or source’. Some medicines look so similar to the genuine product that even healthcare professionals may be fooled.

Falsified medicines may be branded, or presented as generic (unbranded) products used to treat a wide range of conditions, from life-threatening illnesses to common headaches. Some contain the wrong ingredients which may be toxic; others have no or insufficient active ingredients ­– or too much. Fake medicines could potentially poison you, be fatal, or may mean that treatment fails.

Falsified medicines are found all over the world and are always illegal. They are recognised by the WHO and EU institutions as a growing threat to the public and potentially very dangerous.

For detailed information, see Falsified medicines.

Biologics or biological medicines are made from living cells. These new, innovative drugs are being developed to treat illnesses such as cancer, multiple sclerosis and Parkinson’s. Because they use living cells, no two biologics made different cell lines will be alike. They are also very sensitive to the manufacturing process. Changing this can alter the final compound and the way it works in the body.

Biosimilar medicines are follow-on versions of the original biologics. They do not use the same living cells as biologics but are designed to treat illnesses in the same way.

The drug companies who manufacture conventionally made medications know their exact chemical make-up. In contrast, most biologics are complex mixtures that are not easily identified. For this reason, patient safety may be a concern. If you are interested in learning more about these new forms of treatment, you should consult your doctor.

• VIDEO – CNS Academy: How to manage your medication in Parkinson's Disease