Some people taking medication may make antibodies against that drug, reducing or neutralising the drug's effectiveness.

NHS continuing healthcare is health and social care that is arranged and paid for solely by the NHS and delivered at your home or in a residential setting. It is available if you live in England and are assessed as having long-term complex health needs.

The NHS Low Income Scheme helps people who are not exempt from charges but who may be entitled to full or partial help if they have a low income. Find out more in this A-Z entry.

Health and social care are organised and funded by the devolved governments in England, Wales, Northern Ireland and Scotland.

Nocturia is the need to wake up multiple times during the night to empty your bladder. It can be common in multiple sclerosis (MS), particularly if you need to use the toilet often during the day (frequency) or if you have difficulty emptying your bladder.

Nuedexta (dextromethorphan/quinidine) is a drug used to treat pseudobulbar affect – uncontrolled laughing or crying – a potential symptom of multiple sclerosis. It was licensed by the European Medicines Agency in June 2013, however it was withdrawn from use in the European Union in 2016.

Nystagmus is the involuntary movement of the eyes, causing them to flick rapidly from side to side, up and down, or in a rotary manner. It can be a visual symptom of multiple sclerosis.

Studies have shown obesity can increase your risk of getting MS, make your symptoms more severe, and accelerate disease progression. By being aware of your weight and taking steps to stay healthy, you are making a real difference to your MS.

Occupational therapists (often known as OTs) aim to help people with multiple sclerosis continue to live life as fully as possible, providing practical support to overcome whatever barriers they may find in their daily activities.