Pathophysiology and Drug Therapy for Alzheimer’s and Other Diseases Treated with Cholinergic Agents

What does the CNS include?

The brain and spinal cord

What does the PNS include?

Efferent and afferent neurons

What is the efferent portion of the PNS divided into?

The autonomic and somatic nervous systems

Autonomic Nervous System (ANS)

Controls involuntary activities in smooth muscle, secretory glands, and visceral organs, Functions in homeostasis, stress response (fight or flight), and body tissue repair

What are the primary neurotransmitters of the ANS?

Acetylcholine and norepinephrine

What neurotransmitter is associated with the Sympathetic Nervous System?

Norepinephrine

What neurotransmitter is associated with the Parasympathetic Nervous system?

Acetylcholine

Myasthenia Gravis

Chronic autoimmune neuromuscular disease that involves muscle weakness that increases during periods of activity and improves after periods of rest. A result of a defect in the transmission of nerve impulses to muscles

What drug is commonly used to treat Myasthenia Gravis?

Pyridostigmine

What is the action of Pyridostigmine?

Prevents the breakdown of acetylcholine, increases muscle strength and endurance

What are symptoms of a Cholinergic Crisis?

Muscle weakness, excessive salivation, diaphoresis, lacrimation, n/v/d, abdominal cramping, bradycardia, and respiratory distress

What is the antidote for a cholinergic crisis?

Atropine

Alzheimer’s Disease

Most common form of dementia. Caused by a deficiency in cholinergic function in the cortex and basal forebrain. Neuropathologic hallmarks are plaques and neurofibrillary tangles

What is an early symptom of Alzheimer’s Disease?

Difficultly remebering newly learned information

What is the prototype for Cholinesterase Inhibitors?

Donepezil

What is the prototype for N-methyl-d-aspartate receptor antagonists?

Memantine

What is the action of Donepezil?

Increases amount of acetylcholine in the brain

What are nursing considerations for Donepezil?

Medication should be taken at night, avoid NSAIDs to prevent GI bleeding and ulceration, dose will start low and increase, and medication should be taken with food

What is the mechanism of action of Memantine?

Blocks the action of excess glutamate, a neurotransmitter that can be neurotoxic at high levels

What are the adverse effects of Memantine?

CNS effects, GI symptoms, urinary incontinence, skin rash, back pain, and dyspne/bronchospasm