CHOLINERGIC AND ANTICHOLINERGIC DRUGS


CHOLINERGIC DRUGS

Actions and Uses:
Cholinergics stimulate the parasympathetic nervous system. They affect both the muscarinic and nicotinic receptors. There are direct and indirect acting cholinergic drugs. Direct acting drugs act on the receptors to activate a tissue response. Indirect acting drugs inhibit the action of the enzyme cholinesterase by forming a chemical complex. The major uses of this drug are to stimulate the bladder and gastrointestinal tone. They can also constrict the pupils of the eye and increase neuromuscular transmission. These drugs can also decrease heart rate and blood pressure.

Side Effects and Adverse Effects:
Some side effects of cholinergics include: nausea, vomiting, diarrhea, sweating, salivation, frequent urination, rash, blurred vision, and abdominal discomfort. These drugs can also cause hypotension, bradycardia, and muscle weakness. Some life threatening adverse effects include, heart block and cardiac arrest.

Nursing Implications:
A nurse must assess and record intake and output. A decrease in urinary output must be reported due to the fact that it may be related to urinary obstruction.

Give cholinergics one hour before or two hours after meals.

Ensure that the nurse has IV atropine sulfate 0.6mg available as an antidote for overdose. Be observant for signs of overdose which include: salivation, sweating, abdominal cramps, and flushing.

ANTICHOLINERGIC DRUGS

Actions and Uses:
Anticholinergic drugs inhibit the actions of acetylcholine by occupying the acetylcholine receptors. Many major body tissues and organs are affected by this group of drugs. These include: the heart, respiratory tract, gastrointestinal tract, urinary bladder, eyes, and exocrine glands. These drugs block the parasympathetic nerves so that the sympathetic nervous system is dominant. They have the opposite effect of cholinergic drugs. They promote urinary retention, dilation of pupils, and an increase in pulse rate.

Side Effects and Adverse Effects:
Some common side effects of anticholinergic drugs include dry mouth, decreased perspiration, blurred vision, tachycardia, constipation, and urinary retention. Some adverse reactions are nausea, headache, dry skin, hypotension, hypertension, impotence, photophobia, and coma.

Nursing Implications:
A nurse is responsible for assessing fluid intake and output. The client needs to void before taking any medication. Report decreased urine output because anticholinergics can cause urinary retention. It is important that the client maintain adequate fluid intake.

Patients taking anticholinergics need to be advised to avoid hot environments and excess physical activity because elevations in body temperature may result in deminished sweat gland activity.

Also advise the patient to not drive a motor vehicle because drowsiness is common with anticholinergics.

REFERENCES:
Kee, Joyce L., Hayes, Evelyn R., & McCuistion, Linda E. (2009). Pharmacology: A Nursing Process Approach (6th ed.), (pp. 282-293). St. Louis, Missouri: Saunders Elsevier

Edited By: Grant Gardner