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Occipital lobe epilepsy

The occipital lobes are a part of the brain responsible for sight. In this type of epilepsy, seizures start in the occipital lobe. These seizures can cause visual disturbances like sensations of colours, flashes, shapes and pattern.

People can also experience:

  • More complex hallucinations and illusions like animals, scenes and people (including self images).
  • Spatial distortion
  • Alterations in size and shape
  • Seeing object repeatedly
  • Movement of objects
  • Objects breaking up
  • Blindness accompanied by the illusion of lights and colours
  • Forced head and eye turning (with the patient believing the hallucination is being tracked voluntarily
  • Rapid blinking or eyelid flutters
There can be associated headaches and nausea and these seizures can be confused with migraine.

See Also: Simple Partial Seizures

Older people with epilepsy

Often there is no known cause for epilepsy. However, a physical cause is more likely to be found if you have developed epilepsy later in life. Epilepsy can be caused by things like strokes or dementia in older people.

Memory can also become a problem in later life. Epilepsy and the side effects of medication sometimes make this worse.

There are simple ways to help with memory problems such as:

  • keeping a diary
  • using lists or post-it notes
  • using pill dispensers and setting alarms to help you to take your anti-epileptic drugs (AEDs) on time

There are other methods you can try to improve memory. For more information get our Epilepsy and Memory guide. If you or your family or friends become concerned about your memory, speak to your doctor.

For more information on older people with epilepsy, please also see our Epilepsy and later life guide.  You may also find our Epilepsy in Later Life - A good Practice Guide for health professionals useful.

Olfactory sensations

Olfactory sensations are smells. People can experience odd smells when they are having a simple partial seizure. This can sometimes be a warning that they will have another kind of seizure.

See Also: Simple Partial Seizures.

Operations and surgery for epilepsy

For a small number of people surgery is a possible treatment. This depends on where seizures start in the brain. Removing the part of the brain which is causing the seizures may stop them. You will usually only be considered for surgery if you have not responded well to a combination of drugs over a period of time.

If your doctor thinks you could benefit from surgery you will have a pre-surgical assessment. First of all, the neurologist needs to check if the specific area of your brain can be operated on. They will want to work out how the operation may affect other brain functions, for example, your speech and memory. They will consider how successful the surgery is likely to be.

Surgery is usually not suitable for people with generalised epilepsy. This is because all of the brain is involved with these types of seizures.

Oxcarbazepine (Trileptal)

Oxcarbazepine is a generic drug used to treat partial and secondary generalised seizures. The brand name for this drug is Trileptal.

Side effects are a concern for many people with epilepsy. Most people, who do experience side effects, find that they are mild and may reduce as their body becomes used to the medication. It is important to discuss any concerns you have regarding side effects with your doctor.

Known side effects for oxcarbazepine can include skin rash, double vision, unsteadiness, headache, nausea, diarrhoea and confusion.

With all anti-epileptic drugs (AEDs) it is important to make sure you get the same make each time. There can be small differences between different versions or makes of each drug. A different make can trigger a seizure for some people. If the packaging of your AEDs looks different speak to your pharmacist, epilepsy specialist nurse, GP or consultant about this. There is more information on AEDs in our Epilepsy and treatment guide.

Oral
This means 'by mouth'. Sometimes medicines that are swallowed are called 'oral medication'.
Osteoporosis and Osteomalacia

Osteoporosis is brittle bone disease. Osteomalacia is a softening of the bones. Both are possible side effects of some anti-epileptic drugs (AEDs)such as carbamazepine, phenobarbital, phenytoin and sodium valproate. These epilepsy drugs may lower the levels of Vitamin D in the blood. This can cause a loss of bone mass in some people, increasing the risk of fractures.

If you have been taking any of these drugs for a long time your GP may suggest a bone scan especially if you are at risk of developing osteoporosis or osteomalacia. Women who are going through the menopause, or men and women in later life are more at risk.

For more information on osteoporosis see check out the National Osteoporosis Society website.

Overseas travel

There is no evidence that flying triggers seizures, but other triggers may affect you when travelling. These include lack of sleep, missing meals or dehydration. If you have regular seizures let the cabin crew know in advance.

Take plenty of epilepsy medication for your trip and extra in case your journey is delayed. Other countries may not have your medication. Check this before you go. Take two lots of medication. One for your hand luggage and one in your suitcase, in case either go missing.

Your GP can arrange extra supplies. Keep your medication in its original container. A letter from your GP or repeat prescription is helpful in case customs ask you about the medication you are carrying.

Make sure you take your medication at the usual time. If you are flying to a different time zone get advice from your GP about how to change the timing of your medication.

Get advice from your GP about any vaccinations or medicines you may need for your trip. For example, there is some evidence that anti-malaria drugs can cause problems for people with epilepsy.

It is important for anyone travelling abroad to get insurance. You should not be charged extra for holiday insurance just because you have epilepsy. The insurance company may ask questions about your epilepsy like the number and type of your seizures. They may decide to charge more depending on the risks involved with your epilepsy. Be aware that some insurance deals that you get when booking your holiday may not cover conditions like epilepsy.

Contact our helpline or see our factsheet on Travelling abroad for more information.

Oxygen deprivation (lack of)
Sometimes a lack of oxygen to the brain can trigger seizures.