ملخص

Classification of treatment of PEPTIC ULCER :

1- Antimicrobial therapy
2-Drugs that decrease gastric acid secretion.
3- Drugs that neutralize gastric acid.
4- Drugs that enhance mucosal defense

Antimicrobial therapy

therapy for patients with peptic ulcer disease who are infected with H. pylori requires antimicrobial treatment.
Eradication of H. pylori results in rapid healing

either triple therapy consisting of a proton pump inhibitor with either metronidazole or amoxicillin plus clarithromycin, or quadruple therapy of bismuth subsalicylate and metronidazole plus tetracycline plus a proton pump inhibitor

Drugs that decrease gastric acid secretion.

1- H2 receptor blockers2- Anticholinergics (Antimuscarinic) 3- Proton pump inhibitors
H2 receptor blockers
Cimetidine, Ranitidine , Famotidine , Nizatidine
Mechanism of Action:
H2 blockers inhibit acid secretion stimulated by histamine, gastrin, and Cholinomimetics


Drug Interactions:
Side Effects:
Indications
Pharmacological Actions:
I- All (except famotidine) inhibit first pass effect of ethanol that increases its bioavailability (toxicity).
II - Cimetidine inhibits P450 cytochrome system leading to increase toxicity of drug metabolized by this enzyme
I- CNS: sedation, delirium, slurred speech. Associated mostly with cimetidine
II- ENDOCRINE: (only cimetidine) antiandrogenic effect in male and in female ( galactorrhea ).
3- III- BLOOD: blood dyscrasia

1- G.U

2- D.U
3- Gastro esophageal reflex disease (GERD).
4- hypersecretory conditions :
a- Zollinger – Ellison syndrome ( gastrin secreting tumor)
b- systemic mastocytosis
c- multiple endocrine neoplasia ( MEN )
5- pre-anesthesia
6- Controlling symptoms of gastric carcinoma.
7- Hiatus hernia (H.H).
8- Stress ulcer.
9- Iatrogenic ulcer.
1- GIT:
Decrease volume of gastric acid secretion and concentration of pepsin
2-CVS
have little effect on C.O and B.P
3-Immune system
enhancing certain immune response by blocking histamine receptors that decreases mediators release mast cells and basophiles.
4-Effects not related to H2 blocking:
Cimetidine binds to androgen receptors causing gynaecomastia.


Anticholinergic drug used as adjunct in management of peptic ulcer

Proton pump inhibitors:

As Omeprazole
Side Effects:
1.gastric carcinoid tumors
2.low vitamin B12
3.incomplete absorption of calcium carbonate products
4.Erythema multiformis (E.M),
Indications: preferred drugs P.U, GERD, Zollinger – Ellison syndrome.
They inhibit gastric acid secretion by inhibiting H+/K+ ATPase enzyme in parietal cells

Neutralization of gastric acid

Antacids:
Basic substances that decrease acidity by neutralizing HCL, thus protecting ulcer from acid and pepsin as pepsin inactivated in high PH

They provide mucosal protection either through stimulation of P.G production or by binding to identified injurious substance

Amount of antacid given depends on:

1- The rate of acid secretion
2- Presence of food
3- Rate of gastric emptying


Non -systemic: non significantly absorbed, not affect acid – base Balance
As (Mg and Al salts)
Systemic: absorbable cause metabolic alkalosis
As (sodium bicarbonate)

Enhancement of mucosal resistance:

Contraindications: Renal failure and pregnancy
Side Effects: Darkening of tongue, teeth and stool
Indications: D.U and G.U
form a coat that protects from acid, bile and pepsin.
Stimulation of production of mucous and prostaglandin synthesis
Bismuth chelate
Contraindications: Renal failure

Side Effects: Constipation, vertigo and skin rash

Indications: P.U, GERD, GI bleeding, stress ulcer and U.C

Stimulate prostaglandin synthesis and bind to pepsin and bile acid.

Sucralfate
Contraindications: Pregnancy
Side Effects: Dysmenorhea and rash
it prevents G.U in patients taking NSAIDs, chronic D.U and G.U.
It inhibits acid secretion stimulated by histamine
Misoprostol
Antiemetic drugs
1-Anticholinergic : Hyosine or Scopolamine
2-H1-blockers: Cyclizine , Meclizine
3-Dopamine ( D2) antagonists:
-Metoclopramide ( plasil) , Domperidone
4-5-HT3-Blockers : Ondansetron
5-Others : Dexamethasone , methylprednisolone, Diazepam


Prokinetics(drugs promoting GIT motility)
1-Metoclopramide (plasil):
Antiemetic , prokinetic , blocks dopamine receptors in 1-Chemoreceptor trigger zone , enhances actions of Ach on M-receptors in GIT
Indications: Nausea , vomiting , pre-anesthesia
Side effects :
-extrapyramidal dystonia , torticollis , Parkinsonism
Drug interactions:
Atropine(anti-M) as it enhances the action of Ach on M-receptors
2-Domperidone
Dopamine antagonist, antiemetic , prokinetic .
Indications:
Nausea & vomiting of cytotoxic therapy
Side effects :
Dystonia ( less than plasil) , gynaecomastia
3-Cisapride
causes serious arrhythmias.
Indications: GERD .
Side effects : cramps & diarrhea .
4-Erythromycin : antibiotic & prokinetic
5-Bethanechol : cholinomimetic & prokinetic .


6. Substance P/neurokinin-1 receptor blocker
Aprepitant new anti-emetic agent targets the neurokinin receptor in the brain and blocks the actions of the naturalsubstance.

Oculogyric Crisis usually occurs as a side effect of neuroleptic drug treatment.

dexamethasone, increase antiemetic activity when given with high-dose metoclopramide
diphenhydramine with high-dose metoclopramide to reduce extrapyrmidal reaction

Drugs used to induce vomitting :

-Ipecac syrup -Apomorphine

Drugs used in treatment of motion sickness :

A:antichlinergic
1-Hyoscine ( atropine) .
B:H1 blocker
2-Cyclizine & meclizine.
3-Diphenhydramine & dimenhydrinate .
4-promethazine .
Drugs used to treat diarrhea:

Treatment is by inereasing viscosity (pectin, kolin. and chalk). binding. toxins, delaying passage of contents (opioids), and decreasing the motility of intestine (by inhibiting Ach. Release)


Drugs used to treat diarrhea:
Treatment of the cause
Correction of fluids and electrolytes imbalance .

1-Diphenoxylate 2-Diphenoxin 3-Loperamide

Drugs used to treat constipation:
(Laxative , Purgative , Cathartic)
Treatment is by increasing bulk and viscosity of feces and increasing motor activity of the gut.
3-Fecal softeners (emolients):
a-Surface active agent (dioctyl):
b-Liquid paraffin: inert oil
2-Bulking agents :

They increase volume & decrease viscosity , holding water in the gut & stimulate normal reflex.
Two groups of drugs:
I-Hydrophilic colloids
a-Bran: It has the ability to retain water .
Side effects : flatulence , distension , & intestinal obstruction .
b-Methyl-cellulose
II-Osmotic laxatives .
Non-absorbable salts hold water in intestine by osmosis causing distension
a-magnesium sulfate
b-magnesium hydroxide


1-Stimulant (irritant):

Bisacodyl

stimulates sensory endings in the colon
Phenolphthalin: potent stimulant acts directly on colon causing
Senna : stimulates peristalsis .
Glycerol: stimulates rectum.