EPILEPSY DIAGNOSIS. Investigations- EEG, MRI, CT, blood tests. Appendix 1 contains a guide to questions to help with diagnosis

Transcription

1 EPILEPSY DIAGNOSIS All adults with a recent-onset suspected seizure should be seen urgently by a specialist. The seizure type(s) and epilepsy syndrome, aetiology and co-morbidity should be determined. Diagnosis should be made be a specialist in epilepsy Investigations- EEG, MRI, CT, blood tests. Appendix 1 contains a guide to questions to help with diagnosis

2 TREATMENT Empowering people to manage their condition. Adults with epilepsy and their families and/ or carers should be empowered to manage their condition as well as possible. Adults should receive appropriate information and education about all aspects of epilepsy. Overall care: Provide an accessible point of contact with specialist services. Take into account race, culture and any specific needs e.g. interpreters Make sure epilepsy specialist nurses are part of the care. Anti-epileptic drugs AED s Overview: Specialist supervision of AED treatment An epilepsy specialist should: Recommend initiation of appropriate treatment Plan continuation of treatment Manage, or provide guidance for, withdrawal Starting treatment After full discussion of risks and benefits with patient and or carers some may choose not to take therapy. Should only be started once diagnosis is confirmed except in exceptional circumstances Treatment is generally recommended after a second epileptic seizure. Choice of drug Consider: Seizure type Epilepsy syndrome Co-medication Co-morbidity Lifestyle Preferences of individual Monotherapy and combination therapy Use monotherapy wherever possible If first treatment is unsuccessful try monotherapy with a different drug. Consider combination therapy if seizures continue after trying monotherapy. Newer AEDs Recommended for adults who have not benefitted from treatment with the older AEDs (carbamazepine or sodium valproate) When they are unsuitable e.g. contraindicated, interactions e.g. oral contraceptives, poorly tolerated, women of childbearing potential. The tpct recommends BRAND NAME prescribing for patients with epilepsy. This does not apply if these drugs are used for other indications.

3 Drug options by seizure type / syndrome Seizure type FIRST LINE Second Line Others drugs to consider Generalised tonic-clonic Absence Ethosuximide topiramate Acetazolamide Phenobarbital Primidone Drugs to avoid Gabapentin Myoclonic Gabapentin Tonic Atonic Focal with/ without secondary generalisation Epilepsy syndrome Childhood absence syndrome Juvenile absence epilepsy Juvenile myoclonic epilepsy Ethosuximide topiramate Gabapentin tiagabine Acetazolamide Phenobarbital Primidone Acetazolamide Phenobarbital Primidone Acetazolamide clonazepam Phenobarbital Primidone acetazolamide Hepatic enzyme inducing AED s-, oxcarbazepine, phenytoin, phenobarbital, primidone, topiramate Barbiturates (Primidone, phenobarbital should rarely be initiated but if required, phenobarbital is preferred.

4 SUMMARY OF DRUGS COMMONLY USED Drug Dose Monotherapy All taken in 2 100mg nocte 2/52 100mg bd 2/52 Continue to increase slowly by mg every two weeks. Once doses of 400mg bd are reached prescribe as modified release. Child: Daily in divided doses: Up to 1 year mg 1-5 years mg 5-10 years mg years 04-1g 300mg bd after food, increased by 200mg daily every 3 weeks Child: Bodyweight up to 20kg, initially 20mg/kg daily in divided doses Under 12, over 20kg, initially 400mg daily in divided doses usual range 20-30mg/kg daily. Adult and children over 12 5mg daily for 2 weeks 10mg daily for 2 weeks 25mg daily for 1 month 50mg daily for 1 month Increasing by 25mg monthly up to 100mg bd. Dose should be divided bd after reaching 100mg daily. divided doses Monotherapy 25mg at night for one week then increased in steps of 25-50mg daily at intervals of 1-2 weeks. Child mg/kg at night for one week then increased in steps of 0.5-1mg/kg daily at intervals of 1-2 weeks. Maintenance dose g daily in 2-4 divided doses. (up to 2g may be needed in some cases) Side effects Interactions Allergic skin reactions, blurred vision, diplopia Dizziness, ataxia, drowsiness, fatigue, headache,, urticaria, nausea, vomiting, anorexia Dose related side effects may be reduced by use of modified release tablets. Hepatic enzyme inducer. Reduces efficacy of oral mg daily (max 2500mg) or 20-30mg/kg daily divided into bd dose Under 12, over 20kg, Max 35mg/kg daily GI problems- nausea, gastric irritation, diarrhoea; weight gain, tremor, drowsiness, ataxia, confusion, headache, lethargy, alopecia Warfarin, mefloquine, chloroquine, cimetidine, Adjuvant therapy with enzyme inducing drugs 50mg once daily for 14 days then 50mg twice daily for a further 14 days, then increased by max 100mg daily every 7-14 days Child above 2 as adjuvant therapy, above 12 as monotherapy-see BNF Monotherapy/ with valproate; mg daily With enzyme inducer mg daily in 2 divided doses. (up to 700mg has been required) Doses of 500mg a day may be needed in some cases. Rash, headache, tiredness, nausea, dizziness, drowsiness, insomnia, visual disturbances, irritability, confusion. Hypersensitivity reaction-rash generally appears within first 8 weeks- fever, lymphadenopathywithdraw lamotrigine Systemic lamotrigine concentrations are approximately halved Adjuvant therapy 25mg at night for 1 week then increased in steps of 25-50mg daily at intervals of 1-2 weeks. Child mg at night for one week then increased to in steps of 1-3mg/kg daily at intervals of 1-2 weeks Monotherapy 100mg daily in 2 divided doses Max 400mg daily Child mg/kg daily, max 15mg/kg daily Adjuvant therapy mg daily, max 800mg daily. Child mg/kg daily. Max 15mg/kg daily Nausea, abdominal pain, dyspepsia, diarrhoea, taste disturbance, weight loss, headache, somnolence Chloroquine and hydroxychloroquine Lithium

5 Tapering of dose Advice to patients contraceptive pill. Decreases levels of levothyroxine, corticosteroids, digoxin, dihydropyridine CCB s, theophylline, warfarin Increased plasma levels of carbamazepine with erythromycin, fluoxetine, fluconazole, cimetidine Reduce by 100mg every 2-4 weeks Blood, hepatic or skin disorders. E.g. fever, sore throat, mouth ulcers, bruising, bleeding, and rash. erythromycin Plasma conc. reduced by carbamazepine No interaction with contraceptive pill. Reduce by 200mg every 2-4 weeks. Pancreatitis, blood or hepatic disorders e.g. vomiting, anorexia, jaundice, and abdominal pain. Monitor LFTs before and for first 6 months of therapy during co-administration of oral contraceptives. May need to increase dose of lamotrigine. Possibility of decreased contraceptive efficacy -avoid contraceptive pillif needed start with advice from secondary care -patients to inform of breakthrough bleeding. Reduce by 50mg every 2-4 weeks Rash or influenza-like symptoms and blood disorders Progesteronesreduced contraceptive effect Ensure adequate rehydration. Myopia, performance of skilled tasks. For all other drugs, see latest BNF REGULAR STRUCTURED REVIEW At least once a year By GP or specialist (QOF) Consider treatment: Effectiveness Tolerability Side-effects Adherence Status Epilepticus in the Community or Primary Care Setting Status epilepticus is defined as seizures which last for more than 30 minutes or a series of seizures which take place without the patient regaining consciousness in between. Discuss first-aid with carers and what to do when faced with prolonged or repeated seizures. Drugs should be administered by a trained healthcare professional or a trained family member or carer according to the individual agreed protocol drawn up by the specialist Secure airway Assess respiratory and cardiac function Administer: First choice - Diazepam rectal solution adult and child over 10kg: 500micrograms/kg up to a maximum of 30mg; elderly 250 micrograms/kg up to maximum of 15mg or Second choice - Midazolam * buccal liquid 10mg/ml (Epistatus) drawn up via oral syringe supplied and administered by the oral route. Adults and children over 50kg: 10mg as a single dose or 5mg if less than 50kg

6 * Currently unlicensed for the treatment of prolonged or repeated seizures Call an ambulance if, required by situation or, response to treatment or, if this is the first episode. UNCONTROLLED SEIZURES PLACE YOUR PATIENT AT HIGH RISK OF DEATH Sudden unexpected death in epilepsy-sudep SUDEP is defined as the sudden, unexpected, witnessed or unwitnessed, non traumatic and nondrowning death in patients with epilepsy, and excluding status epilepticus, in which post-mortem examination does not reveal a toxicological or anatomic cause for death. The risk of SUDEP is 23-fold higher for those patients who have not been seizure free in the previous year compared to those with controlled seizures. Male adolescents are also at increased risk. Review patients with uncontrolled seizures more regularly. Remember seizures can result in severe injuries including falls and burns. Explain dangers of water e.g. avoidance of diving by oneself, having unsupervised baths or swimming alone. WOMEN WITH EPILEPSY Please note that the advice for women applies to ALL women taking AED s regardless of the indication. Examples include the use of carbamazepine for trigeminal neuralgia and topiramate for migraine prophylaxis. Women (and / or family and carers) should be given information about contraception, conception, pregnancy and breast feeding- ideally in advance of sexual activity or pregnancy. Contraceptive advice AED s that INDUCE hepatic enzymes decrease the effectiveness of hormonal contraceptives; thus, progestogen-only oral contraceptives or implant are NOT recommended. AED s that induce hepatic enzymes include: Phenobarbital Primidone Depot injections of progestogen can be used, but should be given every 10 weeks as opposed to 12 weeks. If combined oral contraceptives (COC) are used a minimum of 50mcg of oestrogen is needed increasing to mcg oestrogen if breakthrough bleeding occurs. Consider tricycling; take 63 days of high dose COC consecutively followed by four pill free days. Also encourage use of barrier methods of contraception. Potential harmful effects of AEDs on unborn child Discuss potential harm to unborn child associated with AEDs and assess risks and benefits of different drugs. Provide pre-conception advice as early as possible. Offer folic acid 5mg/ day to women taking AEDS before any possibility of pregnancy. Pregnancy

7 Risk of major foetal abnormality is 2% in general population and 4-6% in pregnant women taking AED monotherapy. The risk increases with AED polytherapy; up to 24% if on 4 drugs. Prescribe folic acid 5mg daily from pre-conception to end of first trimester to reduce the risks of neural tube defects. N.B. 400microgram dose available over-the-counter is NOT sufficient. Refer all new pregnancies to the fast track ante-natal clinic at the Manor People with learning disabilities Should receive same support and care as anyone else with epilepsy Management and treatment should be done by a specialist Driving- DVLA SHOULD BE INFORMED Patients should be advised not to drive after first established seizure. Patients need to have been seizure free for ONE year and have a medical review before they can drive again. Advise patient to return license to DVLA after first confirmed seizure Nocturnal seizures a patient who continues to suffer with only nocturnal seizures can drive once they have been seizure-free in the day for THREE YEARS. HGV Drivers need to be seizure free and off medication for TEN YEARS before they can hold a HGV license. Withdrawal of Anti-Epileptic Treatment SIGN and NICE guidelines recommend that patients should be seizure free for at least two years before withdrawal of treatment is considered. There should be agreement with the patient and the patient should be aware of the risk of relapse and other restrictions such as driving implications. Withdraw slowly- over 2-3 months or longer Withdraw one drug at a time Agree a plan of action in case of seizure. NICE and SIGN guidance contain a prognostic indicator of how likely successful withdrawal will be in patients. This is based upon an RCT (n=1013) of continued AED treatment versus slow withdrawal in adults and children who had been seizure free for at least two years. From this trial it was found that the risk of seizure recurrence on withdrawal is: reduced in those who have been seizure free for longer increased in those taking multiple AED s increased in those with tonic-clonic seizures The DVLA advise that patients should NOT drive whilst undergoing withdrawal of AED s and for 6 months after AED(s) are stopped. If seizure(s) recur, patient needs to be fit-free for ONE year before driving again. Should seizures recur on withdrawal or following withdrawal of medication, the patient should re-start the same drug(s) they were previously maintained on; the dose(s) should be re-titrated according to response. References

8 National Institute for Clinical Excellence. The epilepsies: the diagnosis and management of the epilepsies in adults and children in primary and secondary care. October Scottish Intercollegiate Guidelines Network. Diagnosis and Management of Epilepsy in Adults. April 2003 A national clinical guideline. British National Formulary. Volume 56 September 2008 Anon. Improving epilepsy services and care. MeReC Briefing March 2004; 24: 1-8 Driver and Vehicle Licensing Agency. Neurological disorders. Medical Research Council Antiepileptic Drug Withdrawal Study Group. Randomised study of antiepileptic drug withdrawal in patients in remission. Lancet 1991; 337: Anon. Management of epilepsy in adults. IMPACT Appendix Questions to ask to help with diagnosis

9 What was the timing of the suspected seizure(s)? Date of suspected seizure, if new onset Duration and frequency of seizures If established epilepsy, longest seizure-free period Timing of seizures (e.g. during sleep, on awakening, while awake) Is there an eye-witness description of the suspected seizure(s)? If the suspected seizure was witnessed, it would be helpful for the eye-witness to attend the clinic. What happened before the suspected seizure?* Precipitating factors: emotion/stress television posture drugs menstruation pregnancy fatigue alcohol What happened during the suspected seizure?* Which of the following features occurred? Aura (e.g. epigastric sensation), head turning, jerking (i.e. unilateral/generalised), sensory manifestations, automatisms, psychic/affective manifestations, tongue biting, colour change, incontinence, altered breathing What happened after the suspected seizure?* Post-ictal features: tiredness/sleep, confusion, neurological deficits, headache, limbs Length of time until full recovery? aching What is the patient s medical history? Birth history and early development Febrile convulsions Head injury with loss of consciousness Meningitis Neurological deterioration Psychiatric illness Learning difficulties Encephalitis Other medical conditions (cardiac, stroke, malignancy etc.) What is the patient s drug history/allergies? Current anti-epileptic drugs Concomitant prescriptions Does the patient have any allergies? Previous anti-epileptic drugs (& effects or side effects, if known) Which relevant investigations have been carried out, and what were the results? EEG CT/MRI scans other investigations What were the relevant clinical findings? For example: neurological abnormalities cardiac abnormalities hypertension What information has the patient been given? Implications of epilepsy being diagnosed? Effects on driving/employment If epilepsy, it can be treated in most cases *Please indicate if noted observations were from witness/patient