Gastric system Drugs

Atropine and glycopyrrolate

•↓ salivary secretions

•↓ peristalsis

•Paralytic ileus

• Atropine --should not be used
• Aminopentamide
• Isopropamide
• Propantheline
• Methscopolamine

SE=dry mouth, constipation, increased HR

• Bismuth subsalicylate
• •Coats intestine, mild anti-inflammatory properties
• •Aspirin like – do not use in cats
• •Dark stools
• Kaolin- pectin
• •Coats intestine and is an adsorbent
• Activated Charcoal
• Great adsorbent – adsorbs toxins
• Physiologically inert

• Diphenoxolate
• Ioperamide
• +Increased segmental contractions
• +Lomotil is controlled, atropine added
• +Very effective, relatively safe
• +Dosage is less in cats
• -Do not use in horses or cattle

• Lactulose
• +(also decreases NH₄, liver dz)
• Sodium Phosphate enemas
• - (not in cats)
• MgSO₄
• Magnesium Hydroxide (Milk of Magnesia)

• Phenophthalein
• *aka Ex Lax
• Castor oil

• +Dry water into the intestinal tract in a more natural manner
• Psyllium seed extract
• +forms a gel when mixed with water, used to pass
• out sand that horses eat on accident
• Polycarbophil
• Bran

• Surfactants - reduce surface tension, water soaks into the fecal material
• ie, Ducosate derivatives (DSS)
• gel caps in small animal
• solution for horses and cattle
• Mineral oil
• 1 gallon for horses with colic

CRTZ=Chemoreceptor trigger zone. Outside the blood brain barrier.

Irritants cause dopamine release and stimulation of the vomiting center

• Acepromazine
• Chloropromazine
• Prochloropromazine

-SE: hypotention, sedation

+Act to decrease input to the CRTZ from the vestibular apparatus

• Dimenhydrinate - Dramamine
• Diphenhydramine - Benadryl
• Meclizine - Bonine

• Aminopentamide
• +Blocks Ack peripherally, decreasing input into the CRTZ.
• + May also act to directly block CRTZ
• Atropine - not a good choise

• Metoclopramide
• +Reglan
• +Widely used
• +Blocks the CRTZ
• +Speeds gastric emptying
• +Increases cardiac sphincter tone

• Serotonin antagonists in the vagal system and at the level of the CRTZ
• $$$
• Not widely used

• Apomorphine
• +Causes stimulation of dopamine receptors in the CRTZ. Preferred IV or conjunctivally
• Ipecac syrup
• +Irritates the stomach lining causing vomiting

• CaCO₃
• MgOH
• AlOH
• +Act to neutralize the H+ ions in the stomach
• -Do nothing to prevent acid production
• GERD=Gastro-enteric reflux disease
• Sialorrhea= excessive salivation

• +Block H2 receptors to prevent acid production
• +They do not neutralize and acid already
• produced

• Cimetidine
• Famotidine
• Ranitidine – also stimulates gastric emptying
• slightly

• Pepsin inhibitors
• Sucralfate (Carafate)
• Only works in an acidic stomach
• Do not give with H₂ antagonists

• PG is necessary for intestinal epithelial regeneration
• NSAIDS block normal epithelial healing
• Misoprostol (Cytotec) used to counter ulcer causing potential of NSAIDS
• *Can also stop itching

• lBlock the pumping action of the H+ pump
• lining the gastric mucosa

•Omeprazole (Prilosec)

•Lansoprazole


•Take 1 – 4 days for full effect

• Neostigmine
• •Parasympathetic agonist
• •Stimulates Ach receptors
• •Rumen atony
• •Myasthenia gravis in dogs

• Digestive enzymes
• •Viokase
• •Pancrezyme

Feline megacolon