Pharm Equine GI

T/F Sedatives depress GI motility

True (that is why short acting are often used before surgery)

Name 2 alpha-2s used in horses

Xylazine and Detomidine

Which drug causes ataxia when used for a caudal epidural?

Xylazine

What is Neuroleptanalgesia?

Butorphanol with non-opioid agonist

What type of drug is banamine?

NSAID

Name 3 NSAIDs used for GI conditions?

Flunixin/Banamine & Ketoprofren & Phenylbutazone

What is the dose of NSAIDs in horses?

1.1mg/kg IV 2x a day

Which NSAID is best at treating endotoxemia?

Phenylbutazone

Excessive use of NSAIDs in a stressed horse can lead to _____ colitis

Right Dorsal Ulcerative Colitis

Name some anti-endotoxic drugs

NSAIDs
Hyperimmune plasma (J5 plasma-harvested from horses)
Polymixin B
Pentoxifylline
DMSO (Dimethylsulfoxide)

Polymyxin B

Binds the lipid A portion of endotoxin
At higher doses it has anti-gram neg bacterial activity

Pentoxifyline

Supresses TNFalpha, IL-1 & IL-6 production

DMSO

Radical scavenger & anti-inflammatory effects
Causes hemolysis if given to fast!

Bismuth Subsalicylate (pepto-bismol)

Absorbs toxins
Provides a protective coat
Mild antibacterial action
Anti-diarrhea agent
Usually only used in foals

Activated Charcoal

Absorbs certain toxins and drugs (prevents absorbtion)
Sometimes a laxative is given after 30 mins to hasten removal of toxins

Why shouldn't you give activated charcoal with other drugs?

It may keep them from being absorbed

Di-Tri-Octahedral Smectite (Bio-Sponge)

Intestinal absorbent
Absorbs C. diff & C perfringens toxins
Absorbs toxins, viruses, bacteria and free radicals
Tastes REALLY bad!

Cathartic

An agent for cleansing/purging the bowels

Magnesium Sulfate (Epsom salt)

Laxative
Osmotic agent: draws water into GI lumen
Used in horses with simple impactions
Do NOT exceed 3 days of tx

DSS Diocylt sodium succinate

Laxative
Last resort
Used in severe/refractory cases of impaction

Which laxative is the last resort laxative for impaction? Why?

DSS Diocylt sodium succinate
Last resort because it can cause adbominal cramping and irritation
Dehydration

Why should you not exceed 3 consecutive days of treatment with Magnesium Sulfate?

Mg toxicity or Enteritis

Mineral Oil

Used as a laxative
Lubricates the GI tract

Psyllium (Equine Enteric Colloid)

Laxative
Used for sand impactions
Becomes a gooey mass very quickly

Which laxative is used for sand impaction?

Psyllium (Equine Enteric Colloid)

Can water alone be used as a laxative?

Yes

Cimetidine & Ranitidine

H2 receptors antagonists
Used for healing gastric ulcers

Omeprazole (Gastrogard)

Irreversible proton pump inhibitor

What is the most potent Anti-ulcer med?

Omeprazole (Gastrogard)

Sucralfate (Carafate)

Coats ulcerated mucosa
Increased Prostaglandin E & increased mucous secretion

Lidocaine

Used as a prokinetic, anti-inflam and Analgesic
Used for tx of proximal ileus
Toxic: Muscle fasciculations, ataxia, collapse & seizures

Erythromycin lactobionate

Macrolide antibiotic with motilin receptor agonism

Cisapride

Bendamide
Progressive motility
Does NOT cross the BBB

Bethanechol chloride

Synthetic muscarinic cholinergic agonist
Promotes gastric emptying, & mild cecal and colonic contractions

Neostigmine methylsulfate

Achetylcholinesterase inhibitor
Promotes cecal and large colon motility
Given slowly

Butylscopolammonium bromide (Buscopan)

Anticholinergic, spasmolytic drug
Indicated for control of pain associated with spasmodic colic, flatulent colic or simple impaction colic

Metronidazole

Treatment of clostridial diarhhea

Clostridium ___ is seen in neonatal foals

perfringens is in neonates and difficile is in both

Macrolide AB (clarithromycin, erythromycin, azithromycin)

Used for Lawsonia & Enterocolitis caused by Rhodococcus equi

Which macrolide is best for treatment of lawsonia and rhodococcus?

Clarithromysin +/- rifampin

Chloramphenicol

Treatment of Lawsonia
Humans need to be careful bc of aplastic anemia

Oxytetracycline

Indicated for use against Potomac Horse Fever (neorickettsia resticii)
This can also be the first step in treatment of lawsonia