1. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Anticonvulsants and Antiparkinsonism Drugs Chapter 5

2. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Anticonvulsant Drugs  Prevent convulsions or seizure Partial or focal seizure  Arise from a localized area in the brain and cause specific symptoms  Can spread to the entire brain and cause a generalized seizure Generalized seizure  Absence  Myoclonic  Tonic-clonic

3. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Psychomotor Seizures  Occur most often in children.  Aura may precede the event.  Most common motor symptom is drawing or jerking of the mouth and face.

4. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins EpilepsyEpilepsy  Permanent, recurrent seizure disorder

5. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Actions of Anticonvulsants  Reduce the excitability of the neurons of the brain

6. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Uses of Anticonvulsants  Used to control seizure activity, but often a patient will not respond well to one drug, and another drug or a combination will be tried  Dose adjustments often are needed to find the correct level of control

7. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Anticonvulsants  The most common adverse reaction is sedation. Can range from drowsiness to somnolence  Agitation rather than sedation may occur in some patients.  Adverse reactions may be reduced or eliminated with therapy or a decrease in dose.

8. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Anticonvulsants  Benzodiazepines also can cause sedation  Adverse reactions can be dose dependent and include: Anorexia Constipation or diarrhea  A health care provider should be notified if: Unusual bruising or bleeding Fever Sore throat Rash Mouth ulcers

9. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Anticonvulsants  Hydantoins (phenytoin) are the most commonly prescribed anticonvulsants, and adverse effects include: Nystagmus Ataxia Slurred speech Mental changes Gingival hyperplasia Blood dyscrasias

10. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Anticonvulsants  Succinimides often cause gastrointestinal symptoms  Other adverse reactions: Mental confusion Personality changes Pruritus Urticaria Urinary frequency Weight loss Hematologic changes

11. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Anticonvulsants Miscellaneous anticonvulsants –Lamotrigine – severe and potentially fatal rash

12. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticonvulsants  Care should be taken with barbiturate use in patients with liver, kidney, or neurologic disorders or pulmonary disease.  Barbiturates are used with caution in hyperactive children.  Barbiturates will have an additive effect if used with alcohol or other CNS depressants.

13. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticonvulsants  Care should be taken with benzodiazepine use in patients with psychoses, acute narrow angle glaucoma, liver or kidney disease, or neurologic disorders.  Benzodiazepines should be used with caution in elderly or debilitated patients.  Alcohol and other CNS depressants can also have an additive effect when used with benzodiazepine.  Benzodiazepines interact with a number of other medications.

14. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticonvulsants  Hydantoins are contraindicated in patients with: Sinus bradycardia Sinoatrial block Second- and third-degree AV block Adams-Stokes syndrome Liver disease Pregnancy and lactation

15. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticonvulsants  Hydantoins have an additive effect with alcohol and other CNS depressants.  Phenytoin should be used with caution in patients with: Hypotension Severe myocardial insufficiency Hepatic impairment  Phenytoin interacts with many different drugs.

16. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticonvulsants  Succinimides are contraindicated in patients with bone marrow depression or hepatic or renal impairment and during lactation.  Additive effect with alcohol, antidepressants, and narcotics  Concurrent administration with other anticonvulsants may require a dosage adjustment.

17. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticonvulsants  Miscellaneous anticonvulsants are used cautiously in patients with: Glaucoma or increased intraocular pressure History of cardiac, renal, or liver dysfunction or psychiatric disorders  Carbamazepine Contraindicated in patients with bone marrow suppression or hepatic or renal impairment Interacts with several other drugs

18. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticonvulsants  Valproic acid Contraindicated in patients with renal impairment  Oxcarbazepine May exacerbate dementia  Lamotrigine Interacts with valproic acid  Miscellaneous anticonvulsants have an additive effect when combined with CNS depressants and alcohol.

19. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Patient Management Issues with Anticonvulsants Dosage adjustments may be necessary during initial treatment. Dosage adjustments are based on patient’s response and adverse reactions. Medication must be taken as prescribed. –Do not omit or miss a dose. –Do not abruptly discontinue.

20. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Educating the Patient and Family About Anticonvulsants  Family may be the first to witness seizures.  Keep a record of all seizures.  Anticonvulsants control, but do not cure, epilepsy.  Support groups may be available.  Safety concerns may need to be addressed, such as driving or working conditions.

21. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Educating the Patient and Family About Anticonvulsants  Do not increase, decrease, or omit dose.  Blood levels may need to be monitored.  Do not abruptly discontinue.  These drugs may cause drowsiness or dizziness.  Avoid alcohol.  Carry identification indicating drug use and type of seizures.  Do not use other medications without consulting a health care provider.

22. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Educating the Patient and Family About Anticonvulsants  Hydantoins Brush and floss Make regular dental appointments for oral examination and care Take with food Shake the suspension before use

23. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Educating the Patient and Family About Anticonvulsants  Succinimides Take with food or milk to avoid gastrointestinal upset.

24. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Antiparkinsonism Drugs Parkinson disease – “paralysis agitans” is a degenerative disorder of the central nervous system Caused by a deficiency of dopamine and an excess of acetylcholine within the central nervous system

25. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Actions of Dopaminergic Drugs  Affect the dopamine content of the brain  Dopamine is not effective when given orally since it does not cross the blood-brain barrier.  Levodopa will cross the blood-brain barrier and then converts to dopamine.

26. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Uses of Dopaminergic Drugs  Treat signs and symptoms of parkinsonism  Levodopa is the gold standard.  Carbidopa is always given with levodopa.  Amantadine is less effective than levodopa but more effective than anticholinergics.

27. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Dopaminergic Drugs  Choreiform movements  Dystonic movements  Mental changes: Depression Psychotic episodes Paranoia Suicidal tendencies

28. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Off–On Phenomenon Patient may suddenly alternate between improved clinical status and loss of therapeutic effect Associated with long-term levodopa treatment “ Drug holiday” may be needed

29. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Dopaminergic Drugs  Levodopa is contraindicated in patients with narrow- angle glaucoma and taking MAOIs.  Levodopa interacts with many different drugs.

30. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Dopaminergic Drugs  Levodopa is used cautiously in patients with: Cardiovascular disease Bronchial asthma Emphysema Peptic ulcer disease Renal or hepatic disease Psychosis Lactating patients

31. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Dopaminergic Drugs  Selegiline is used cautiously in patients with psychosis, dementia, or excessive tremor.  Selegiline increases the effectiveness of levodopa when they are taken together.  Selegiline interacts with fluoxetine.

32. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Dopaminergic Drugs  Amantadine is used cautiously in patients with: Seizure disorders Hepatic disease Psychosis Cardiac disease Renal disease  Amantadine interacts with numerous other drugs.

33. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Actions and Uses of Anticholinergic Drugs  Inhibit acetylcholine in the CNS  Used as adjunctive therapy in all forms of parkinsonism  Control drug-induced extrapyramidal disorders

34. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Anticholinergic Drugs  Dry mouth  Blurred vision  Dizziness  Mild nausea  Nervousness

35. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticholinergic Drugs  Contraindicated in patients with: Glaucoma Pyloric or duodenal obstruction Peptic ulcers, prostatic hypertrophy Achalasia Myasthenia gravis Megacolon

36. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Anticholinergic Drugs  Use with caution in: Older adults Cardiovascular disease (tachycardia, cardiac arrhythmias, hypertension, hypotension) Urinary retention Decreased liver or kidney function Obstructive disease of the gastrointestinal tract

37. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Actions and Uses of COMT Inhibitors  Catechol-O-methyltransferase (COMT) inhibitor  Thought to prolong the effect of levodopa by blocking the enzyme COMT, which would otherwise eliminate the dopamine  Used as an adjunct to levodopa/carbidopa  Easily crosses blood-brain barrier

38. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of COMT Inhibitors  Disorientation and confusion  Light-headedness  Dizziness  Dyskinesias  Hyperkinesias  Nausea and vomiting  Hallucinations  Fever

39. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of COMT Inhibitors  Contraindicated during lactation  Associated with liver damage and liver failure  Used with caution in patients with hypertension, hypotension, and decreased hepatic or renal function

40. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Actions and Uses of Dopamine Receptor Agonists  Exact mechanism not understood  May mimic the effects of dopamine in the brain  Used for Parkinson disease

41. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Adverse Reactions of Dopamine Receptor Agonists  Nausea  Dizziness  Postural hypotension  Hallucinations  Somnolence  Vomiting  Confusion  Visual disturbances  Abnormal involuntary movements  Headache

42. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Dopamine Receptor Agonists  Contraindicated in patients with severe ischemic heart disease or peripheral vascular disease  Use with caution in patients with: Dyskinesia Orthostatic hypotension Hepatic or renal impairment Cardiovascular disease History of hallucinations or psychosis

43. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Contraindications, Precautions, and Interactions of Dopamine Receptor Agonists  Increased risk of CNS depression  Increase the effects of levodopa when coadministered  Interact with ciprofloxacin and phenothiazines  Pramipexole interacts with a number of medication  Ropinirole interacts with estrogens

44. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Patient Management Issues with Antiparkinsonism Drugs  History obtained from patient can be unreliable.  Baseline physical assessment needed.  Drug therapy needs careful monitoring.  Some patients communicate poorly.  Observe the patient for outward changes that may indicate adverse reactions.  Symptoms may be communicated through changes in posture and facial expression.

45. Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Educating the Patient and Family About Antiparkinsonism Drugs  The home environment must be examined to make it least likely to result in accidents or falls.  Medication should be taken as prescribed.  Sudden changes in behavior can indicate hallucinations, depression, or other psychotic episodes.  Observe the patient for adverse reactions.