Transcript Drugs acting on digestive system

Drugs Acting on the Gastrointestinal
tract
GIT related disorders
Other disorders
In appetence
Appetite stimulants
Different drugs
Diarrhoea
Acids
Antidiarhoeal
Antiacids
Indigestion
Constipation
Laxatives and cathartics
Digestants
Vomiting/Emesis
Emetics/antiemetics
Introduction
 Most of the GIT disorders are related
with motility
 Non specific treatment of GIT disorders
may be useful by
- Correction of fluid and electrolyte
balance
- Rest of the GIT
- Diet modification
- Provision of nutritional support
- Alleviation of visceral pain
Appetite stimulants
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Benzodiazepines
Cyproheptadine
Glucorcorticoids
Bitters
Zinc
Appetite stimulants
 Benzodiazepines
- Diazepam
- Oxazepam
Mode of action- Stimulation of GABA
Clinical use – Most in cats, less in Horses, dogs and
goats
Admn – Oral
Cyproheptadine
It suppreses the satiety center in the
brain by acting as serotonin and
Histamine (H1) antagonist
Clinica use – in cats and human, not in
dogs
Adverse effects – Excitement and
aggressive behavior in some cats
Glucocorticoids
Examples
- Prednisolone
- Dexamethazone
Mode of action – may be induce
euphoria
Adverse effects – Immunosuppression
and gastric ulcers may result
Bitters
These are plant derived compounds
containing alkaloids such as Nux
vomica
Mode of action – They stimulate
salivation
Zinc
It is essential for the sensation of taste;
therefore zinc supplements may
increase appetite in zinc-deficient
animals
Anorexigenic substances
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For effective anorexigenic substances include amphetamine
- member of the group phenylalkylamines with central and
peripheral sympathomimetic properties. Its mechanism of
action is mainly in the fact that it enhances the release of
nerve endings of norepinephrine and dopamine, and inhibits
the reuptake of them. At the same time stimulates the
central adrenergic receptors and dopamine receptors,
leading to inhibition of the hunger center. In addition,
amphetamine has a stimulating effect on the cerebral
cortex, and perhaps secondarily inhibits the hunger center.
However, due to the fact that amphetamine refers to the
active psychoactive drugs and has a pronounced peripheral
sympathomimetic properties when applied arise anxiety,
insomnia, tachycardia, increased blood pressure may
develop physical drug dependence. Therefore, as an
amphetamine like drugs are not used.
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A series of analogues of amphetamine (fenilalkilamina derivatives) with
more selective anorexigenic effects, for example Fepranon (amfepranon).
Pharmacologically similar to it fenaminom, but inferior to him in ability to
reduce appetite. The mechanism anoreksigennogo fepranona effect is
similar to that of amphetamine, but it is less stimulates the central
nervous system. In addition, it is not as pronounced Adrenomimeticalkie
peripheral effects. Use of the drug combined with a decrease in food
intake. Enter Fepranon inside, usually for 30-60 minutes before eating.
To avoid sleep disturbance ¬ taking it out in the first half of the day.
Treatment should be under the supervision of a physician. When using
fepranona possible side effects of the cardiovascular system
(tachycardia, hypertension, arrhythmias) and CNS (anxiety, sleep
disturbance). Marked the development of addiction and physical drug
dependence. The drug is contraindicated in severe arterial hypertension,
coronary heart disease, cerebrovascular disorders, with glaucoma ¬ ME,
thyrotoxicosis, nerve diseases, leading to increased impact ¬ wake CNS
and convulsions.
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Anorexigenic property is possessed and back ¬ selective
inhibitors of neuronal uptake of serotonin. However,
previously known drugs in this group due to the side effects
are no longer used. In Examples include fluoxetine, used
primarily as anti ¬ tidepressanta. However, it has severe
and anorexigenic effect.
Sibutramine (Meridia) is an anorexigenic agent
ingibiruyushim reverse neuronal uptake of norepinephrine,
serotonin and dopamine. Pony ¬ zhaet concentration in
serum uric acid, a beneficial effect on blood lipids. Quickly
and well (~ 77%) is absorbed from the digestive tract. Most
of the drug is metabolized in the first pass through the
liver. Of formed metabolites have anoreksigennoy activity.
Sibutramine and Me ¬ metabolite is largely bound to
plasma proteins blood was isolated ¬ are in the kidneys. Of
the side effects observed pressor effect, tachycardia, ¬
solution violation of sleep, headache, CNS stimulation,
constipation, etc.
ANTACIDS
They include
- Acid secretion inhibitors
- Proton pump inhibitors
- Locally acting antacids
- Gastric protectants
Acid secretion inhibitors
Histamine (H2) blockers
- Cimetidine
- Ranitidine
Mode of action – H2 stimulates the
proton (acid) pump in parietal cells.
H2 blockers block the H2 receptors
hence decrease HCL secretion
Proton pump inhibitors
Example Omeprazole
Mode of action – they inhibit H+-K+ATPase hence reduce hydrogen
secretion
Locally acting antacids
They include
- Aluminum salts (Aluminum hydroxide,
Aluminum carbonate, Aluminum
silicate)
- Magnesium salts (Magnesium oxide
(milk of magnesia), Magnesium
tricilicate
- They act by neutralizing gastric HCL
Gastric protective
Example is Sucralfate
This is a sucrose sulfate-aluminum
hydroxide complex
Mode of action – it polymerizes to a
viscous gel. The sulfate groups bind
to proteins in ulcerated tissue and
protect ulcers from acids and pepsin
DIGESTANTS
Introduction
Definition - Digestants are a group of
drugs used to promote the process of
digestion in the gastrointestinal tract
They include
- Pancrelipase
- Bile acids and salts
Pancrelipase
It consists of pancreatic enzymes (e.g.
lipase, amylase, trypsin)
Clinical use – Used to treat exocrine
pancreatic insufficiency in dogs, cats
and birds
Bile acids and salts
They include;
- Bile acids (e.g. cholic acid,
chenodeoxycholic acid)
- Semisynthetic bile acid derivatives
(e.g. dehydrocholic acid)
- Sodium salts of bile acids
Mode of action – they stimulate
choleresis (bile flow)
EMETICS
They include
- Centrally acting emetics
Apomorphine
Xylazine
- Peripherally acting emetics
Sodium Chloride
Syrup of ipecac (from Ipecacuanha)
Copper sulfate, zinc sulfate,
hydrogen peroxide
ANTI EMETICS
They include
- Antidopaminergic agents
- Antihistamines
- Anticholinergic agents
- Miscellaneous antiemetics
Antidopaminergic agents
Phenothiazine drugs
Acepromazine
Chlorpromazine
Promazine
Prochlorperazine
Metoclopramide
Butyrophenones
Droperidol
Haloperidol
Antihistamines
 Dimenhydrinate
 Diphenhydramine
 Promethazine
Anticholinergic agents
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Aminopentamide
Propantheline
Isopropamide
Darbazine (isopropamide plus
prochlorperazine)
Miscellaneous antiemetics
Intestinal protectants and adsorbents
(kaolin, pectin, bismuth salts)
Locally acting gastric antacids (Mg
hydroxide, Mg silicate, Al hydrox., Al
silicate) may reduce vomiting caused
by gastric hyperacidity
LAXATIVES AND CATHARTICS
They are used for
- Relief of acute non-dietary
constipation
- Removal of poisons from the
gastrointestinal tract
- Prevention of Tenesmus in
advanced pregnancy or prolapse
- Evacuation of bowel prior to surgery
or radiography
LAXATIVES AND CATHARTICS
They include
- Osmotic cathartics
- Irritant cathartics
- Bulk laxatives
- Lubricants
- Surfactants
Osmotic cathartics
Examples
- Mg sulfate (Epsom salt), Mg oxide
- Sodium sulfate (Glauber’s salt)
- Polyethylene glycol electrolyte
solutions
- Sodium phosphate and sodium
tartrate mixtures (fleet enemas)
Irritant cathartics
Examples
- Castor oil
- Aloe
- Senna
- Cascara sagrada
Bulk laxatives
Examples
- Methylcellulose
- Agar
- Psyllium
- Wheat bran
Lubricants and surfactants
Lubricants - Mineral oil (liquid
petrolatum) and white petrolatum
Surfactants – Docusate
ANTI DIARHOEAL DRUGS
They include
- Opiates
- Anticholinergic agents
- Protectants and adsorbent agents
Opiates
They include
- Paregoric – a camphorated tincture
of opium
- Diphenoxilate
- Loperamide
- Codeine
Anticholinergic agents
They include
- Methoscopolamine
- Aminopentamide
- Propantheline
- Isopropamide
Protectants and adsorbent agents
Preparations
- Kaolin-pectin suspensions
- Bismuth sub-salicylate
DRUGS USED TO TREAT
INFLAMMATORY BOWEL DISEASE
Examples
- Sulfasalazine
- Olsalazine
- Tylosin
- Metronidazole
DRUGS FOR TREATMENT OF RUMINANT
GASTROINTESTINAL DISORDERS
Several groups
- Agents for inducing closure of the
esophageal groove
- Ruminotorics
- Rumen antacids
- Rumen acidifiers
- Viscosity-altering (antibloat) agents
Agents for inducing closure of the
esophageal groove
Example
- Milk
- Sodium bicarbonate (10% to calves)
- Copper sulfate (5% to calves, 2% to
lambs)
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Ruminotorics
They include
- Bitters
- Cholinergics
- Opiate antagonists (eg naloxone)
- Rumen fluid transfer
Rumen antacids
Examples include
- Magnesium oxide
- Magnesium carbonate
- Aluminum hydroxide
- Calcium carbonate
- Ammonium carbonate
Rumen Acidifiers
Example
- Vinegar
- 4%-5% Acetic acid
Viscosity-altering (anti-bloat) agents
Preparations include
- Poloxalene
- Polymerized methyl silicone
- Mineral oil and
- Vegetable oil (e.g. soybean, peanut,
sunflower oil).