4. Central Nervous System Drugs: Part 1
Autonomic Nervous System Drugs
Drugs Used to treat Seizures
Drugs Used to treat Parkinson’s Disease
Analgesics

6. Autonomic nervous System Drugs
Adrenergic (norepinephrine)
Alpha Receptors
Beta Receptors
Cholinergic (acetylcholine)
Nicotinic Receptors
Muscarinic Receptors

7. Classifications Sympathomimetic Parasympathomimetic
Adrenergic agonists
Adrenergic antagonists/Alpha or beta blockers
Parasympathomimetic
Cholinergic agonists
Cholinergic antagonists/Muscarinic or Nicotinic blockers

8. Parasympathomimetics
Used to treat Myasthenia Gravis
pyridostigmine (Mestinon)
Use to increase urination
bethanechol (Urecholine)

9. Anticholinergics
Atropine:
Therapeutic Uses
Increased heart rate
Bronchodilation
Decreased GI Motility
Pupil dilation
Side Effects –
Dry mouth
Constipation
Urinary retention
scopolamine (Hyoscine)
benztropine (Cogentin)
Note: Therapeutic effects can be side effects. For example, if the person is taking the drug pre-operatively to decrease gastrointestinal secretions, increased heart rate is not a desired/therapeutic effect, it is a side effect.

10. Sympathomimetics
Used to treat respiratory and cardiovascular conditions
stimulates heart
causes bronchodilation
Some drugs are selective for receptor subtypes
phenylephrine (Neosynephrine)
albuterol (Proventil)
epinephrine

11. Adrenergic Blockers Primarily used for hypertension
propranolol (Inderal)
metoprolol (Lopressor)

12. Drugs Used to Treat Seizures
Seizure: abnormal electrical activity in the brain
Convulsion: Uncontrolled muscle contractions that may accompany seizures
Delirium Tremens: Due to alcohol withdrawal

13. Antiseizure Drugs
Affect concentration and movement of sodium, calcium and chloride ions across the neuronal cell membrane
Depress excitability of neurons by enhancing GABA receptors.
Note: Some neurotransmitters are inhibitory, not stimulating, GABA is one of those.

14. Classifications Long acting barbiturates First line drug
phenobarbitol (Luminal)
Produce tolerance and withdrawal
Side effects:
respiratory depression
drowsiness

16. Benzodiazepines diazepam (Valium)
Increase the action of the neurotransmitter GABA (gamma amino butyric acid).
Also cause tolerance and withdrawal
Used to treat status epilepticus
diazepam (Valium)
clonazepam (Klonopin)

17. Phenytoin and Similar Drugs
Delay the influx of sodium across the membrane
phenytoin (Dilantin)
Causes hypertrophy of the gums
valproic acid (Depakene)
carbamazine (Tegretol)

18. Succinamides
Block calcium channels, decreasing neuronal impulse transmission
Ethosuxinimide (Zarontin)
Typically used in combination with other drugs
May require dosage adjustment of the other anticonvulsants

19. Drugs Used to Treat Parkinson’s Disease
Parkinson’s Disease is caused by the destruction of dopamine producing neurons in the CNS which causes motor disturbances.
SX:
Akinisia
Shuffling gait
Pill rolling
Mask like face
Parkinson's

20. Drug Therapy Two fold approach Dopaminergic Drugs
Enhance dopamine production or replace it
Decrease the influence of acetylcholine
Dopaminergic Drugs
Anticholinergic Drugs

21. Anticholinergics Used first before the dopaminergics
Block the action of acetylcholine thereby restoring the balance
Examples:
trihexyphenidyl (Artane)
Benztropine (Cogentin

22. Anticholinergic Side Effects
Dry mouth, blurred vision, (mydriasis), eye pain (acute glaucoma), photophobia, constipation, urinary retention, tachycardia, orthostatic hypotension, anhidrosis.

23. Dopaminergics Replace dopamine or restore its action in the brain
Examples:
levodopa (Laropa)
bromcriptine (Parlodel)

24. Side effects: Dyskinesia

25. Dementia Causes Alzheimer’s Disease Stroke AIDS Atherosclerosis
Medications
Parkinson’s
Alzheimer's Disease
Symptoms caused by loss of acetylcholine
Current medications result in only minor improvement

26. Acetylcholine Function
Drugs
Ache inhibitors
donepezil hydrochloride (Aricept)
tacrine (Cognex