Drug acting on GIT

• Appetite stimulant – agent that enhance feed intake
• Anorexigenic agents – appetite suppressant
• Emetics – drug that induces vomiting
• Antiemetics – drug that prevent vomiting
• Antacids - drugs that neutralize excessive gastric acidity
• Adsorbents – chemically inert substances that adsorb dissolved or suspended substances such as gases, toxins, or bacteria
• Astringents – substances that produce proteinprecipitating action limited to the surface of cells. The permeability of the cell membrane is reduced but the cells remain viable
• Protectants – substances that form thin layer over skin or mucous membrane in order to prevent contact with possible irritants
• Carminatives – substances used as flavorings in some drug and food preparations. Their main effect expulsion of gas and reduction of foam formation
• Cathartics – substances that hasten the rate of passage of material through the GIT and promote defecation.
• Appetite stimulant are commonly used in animals manifesting inappetence or anorexia. These symptoms if unabated may result to malnutrition and delays recovery as well as exacerbate underlying disease
• Vitamin B complex, corticosteroid, anabolic steroids – advocated, as appetite stimulants by making the animal feel better
• Zinc – element necessary for normal taste acuity
• Diazepam, Oxazepam - increases feed intake in cat by suppression of satiety center via increase GABA activity and antiserotonergic effect.
• Cyproheptadine- acts as anti-serotonin and antihistamine, can be used in cats and humans
• Diazepam and Oxazepam - less effective in horse, dogs, and goats.
• Bitters - nux vomica, plant alkaloids, and stimulate salivation
• Emetics - For rapid elimination of non-corrosive poison from conscious animal and empty stomach prior to induction of general anesthesia
• Classifications of emetics - Centrally acting and Locally acting
• Centrally acting emetics - stimulate the chemoreceptor trigger zone
• Apomorphine - most reliable emetic in dog
• Apomorphine - produces excitement in cats and is not effective in swine.
• Xylazine - A sedative analgesic with emetic side effect in cats.
• Ipecac syrup - has been used as an emetic but vomiting was not consistent
• 3% hydrogen peroxide - may induce vomiting in 5-10 minutes
• Antiemetic - Agents that control emesis by either central or peripheral action
• Centrally Acting - agents that control vomition by blocking impulses at the higher centers and at the emetic center
• Anti-histamines - blocks histaminergic and cholinergic afferent pathways from the vestibular apparatus to the emetic center
• Anti-histamines prevent motion sickness
• Anti-histamine drugs - Cyclizine HCl, Diphenhydramine, Meclizine HCl
• Antidopaminergic Agents - Blocks dopamine receptors at the CRTZ. They are weak anticholinergic and antihistaminic actions
• Antidopaminergic Tranquilizers - Chlorpromazine, Haloperidol, Droperidol
• Metoclopramide - It also sensitizes the smooth muscles of the proximal GIT to the action of acetylcholine, and improves the coordination of the gastric and duodenal contraction. It increases the speed of small intestinal transit
• Antiserotonergic agents - inhibit serotonin type 3 (5-HT3) receptors located peripherally on vagal nerve terminals and centrally in the CRTZ. Inhibition of 5-HT3 receptors blocks neurotransmission by closing sodium channels.
• Antiserotogenic drugs - ondansetron and dolasetron
• Peripherally acting antiemetics – protects the GI epithelium from further irritation
• Antacids - agents that reduce hydrochloric acid content of stomach by inhibiting acid secretion, neutralizing acids, or coating and protecting the gastric mucosa
• Locally acting antacids - neutralize gastric hydrochloric acid and inhibit pepsin action
• Phosphate deficiency is characterized by muscle weakness and bone demineralization
• Histamine blockers - cimetidine, ranitidine, famotidine