Zusammenfassung der Ressource
Muscarinic Antagonists
- Parasympatholytics
- Competitive Antagonists for
Ach at Muscarinic receptors
- Limited effect at the
Neuromuscular junction or in
Ganglionic transmission
- Nicotinic Receptors
- Sympathetic control
- Similar structure to
Ach, but bulkier
aromatic group in
place of Acetyl group
- Synthetic
- Glycopyrronium Bromide
- Does NOT cross placenta and BBB
- Less CNS effects;
useful in caesarian
sections
- Less tachycardias
- Used in ocular
surgery to prevent
Vagal Stimulation
- Ipratopium Bromide
- Bronchodilation (horses)
- Tx for Chronic
Obstructive Pulmonary
Disease
- Given Inhalation:
Poor absorption,
poor distribution;
minimal side
effects, local effect
in respiratory tract
- Tropicamide
- Mydriatic
- Drug of choice: Intra-ocular exam
- Rapid onset,
Shorter duration
(hrs)
- Cyclopentolate
- Mydriatic
- Cycloplegic
- Tx of Uveitis
- Long duration
of action
- Natural
- Atropine
- Belladona (dilates
pupils, toxic)
- Given I/M, I/V, S/C and P.O.
- Metabolized in Liver;
Excreted by Kidneys
- Tertiary Amine; Ionized at
physiological pH yet crosses
the gut, conjunctival sac (eye),
and BBB
- Premed - to decrease Salivation
- Antispasmodic effect in
the gut; Decreases gastric
secretion
- Not recommended in Horses
- Decreases GI
motility, can cause
central excitation
- Tx of organophosphorus toxicity
- Mydriasis - examination
- Increase HR
- Used with AChEI: to prevent
side effects from Muscarinic
stimulation when AChEI used to
reverse neuromuscular
blockade
- Toxicity
- CNS stimulation: Problem in horse
- Constipation
- Tachycardia
- Urinary retention
- AChEI can be used Tx Toxicity
- Increase Ach to
compete w/ Atropine
- Scopolamine (Hyoscine)
- Used for drying secretions
- Contained in Antispasmodic
Buscopan (+ Dipyrone
metamizole - analgesic)
- Decreases GI contractions
- Antiemetic properties