Anticholinergics

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• decrease secretions before anesthesia
• treat parkinsonism (by blocking the stimulating effects of acetylcholine)
• restore cardiac rate & BP s/p vagal stimulation during surgery
• relieve brady s/p hyperactive carotid sinus reflex
• relieve pylorospasm & hyperactive bowel
• prevent S&S of motion sickness & vomiting
• relax biliary and ureteral colic
• relax bladder detrusor muscles & tighten sphincters
• help to control crying or laughing episodes in pt w/ brain injuries
• relax uterine hypertonicity
• help in the management of peptic ulcer
• control rhinorrhea associated with hay fever
• antidote for cholinergic drugs and for poisoning by certain mushrooms
• ophthalmic agent to cause mydriasis or cycloplegia in acute inflammatory conditions 

• glaucoma
• stenosing peptic ulcer
• intestinal atony, paralytic ileus, GI obstruction
• severe ulcerative colitis
• toxic megacolon
• prostatic hypertrophy, bladder obstruction
• cardiac arrhythmias, tachycardia, myocardial ischemia
• impaired liver or kidney function 
• myasthenia gravis (Low doses of atropine sometimes used in MG to block unwanted GI & CV effects of the cholinergic drugs used to treat it)

Interactions:

• ↑ effects w/ antihistamines, antiparkinsonism drugs, MAOIs, tricyclic antidepressants (all have anticholinergic activity)

Kinetics:

• Well absorbed & Widely distributed throughout the body
• excreted in the urine
• Crosses blood brain barrier

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Drugs:

1. Atropine

Actions:

• Depresses salivation and bronchial secretions
• Dilates the bronchi
• Inhibits vagal responses in the heart
• Relaxes the GI & GU tracts
• Inhibits GI secretions
• Causes mydriasis 
• Causes cycloplegia (paralysis ciliary muscles)

Indications:

• ↓ secretions (before surgery)
• bradycardia
• pylorospasm, ureteral colic, relaxing of bladder
• emotional lability with head injuries
• antidote for cholinergic drugs
• pupil dilation 
• Parkinsonism 

AE:

• Blurred vision, Mydriasis (pupil dilation), Cycloplegia (↓ accommodation reflex), Photophobia 
• Palpitations, bradycardia 
• Dry mouth, altered taste perception 
• Urinary hesitancy & retention 
• ↓ sweating (predisposition to heat prostration)

2. Dicyclomine
- relaxes GI tract; Tx hyperactive or irritable bowel

3. Glycopyrrolate (Robinul)
- adjunct therapy in Tx ulcers

4. Propantheline (Pro-Banthine)
- adjunct in Tx ulcers


5. Scopolamine (Transderm Scop)
- dec N/V associated w/ motion sickness


6. Tiotropium (Spiriva)
 -Tx bronchospasm/COPD

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Nursing Mgmt

• Assess & monitor:
•     CV & Respiratory 
•     CNS (LOC, orientation, reflexes) 
•     GI (Constipation)
•     GU (Urinary retention)
•     Renal 
• Monitor for dry mouth & difficulty swallowing
• elderly & children more susceptible to adverse effect - reduce dose (constipation, urinary retention, heat intolerance, and confusion)
• BUT don't use Dicyclomine w/ kids
• Teaching:

   - void before taking med
   - dry lots of fluids
   - avoid hot temperatures
   - safety precautions for dizziness/blurred vision