Dr.Jannatul Ferdoush

Assistant Professor

Department Of Pharmacology

*ANTIDIARRHOEAL AGENT

• Diarrhoea

•Diarrhoea is a frequent passage of liquid feces resulting from an imbalance between secretion & reabsorption of fluid & eletrolites.

•Causes:

1 .Infective

2.gut motility disorder.

3.IBS & malabsorption due to disease.

4.secretory tumour of GIT-

carcinoid tumour & vipoma.

• TREATMENT APPROACHES OF DIARRHOEA

• 1.For mild to moderate diarrhoea

Maintenance of fluid and electrolyte balance .

• 2.For severe acute diarrhoea

Maintenance of fluid and electrolyte balance.

Antimotility & antispasmotic drug.

antiinfective agents.

• FLUID AND ElECTROLITE TREATMENT

*Oral rehydration therapy with glucose-electrolite solution to maintain the fluid & electrolite balance is the first priority.

*Composition of Oral rehydration salt:

*Na 75mmol/l

*Cl 69mmol/l

*Glucose 75mmol/l

*K 20mmol/l

*Citrate 10mmol/l

*Advantages:

Simple,effective,cheap,readily administered therapy for a potentially fatal condition.

Hypotonic solution, so can cause more Na and water retension.

• ANTIDIARRHOEAL AGENTS

•Antimotility drug—

opioid agonist

•Antispasmotic drug—

M-R antagonist

Direct acting muscle relaxant

•Antiinfective agent—

Erythromycin,ciprofloxacin.

•Adsorbent—

kaolin,pectin,charcoal,methylcellulose.

•Octreotides

• ANTIMOTILITY DRUGS

*Opioid agonist—

loperamide

Diphenoxylate

codeine

Role in GIT motility—

tone & rythmic contraction of the intestine.

propulsive activity.

tone of the large intestine.

secretion of intestine.

All sphincter are contracted.

*OPIOID AGONISTS

• Advantages:

Cannot cross the blood brain barrier, so use only for their action on GIT.

• Disadvantages:

Constipation,abdominal cramp,drowsiness,dizziness.

Large dose Diphenoxylate produces typical opoid effect. So small dose of Atropine is used in combination to discourage overdose.

• Contraindication:

Acute diarrhoea in children—cross BBB—respiratory depression.

IBS—toxic dilatation of the colon.

*ANTISPASMODIC AGENTS

*M-R antagonist—

Atropine

hyoscine

propantheline

dicycloverine

Role in GIT:

Inhibit M-R in the enteric nerve plexus & on smooth muscle.

Inhibit parasympathetic activity.

Decreases spasm of intestine.

*ANTISPASMODIC AGENTS*Direct acting muscle relaxant:

Mebeverine—derivatives of reserpine.

Role in GIT:

direct relaxation action on smooth muscle of intestine.

*Antiinfective agents* Diarrhoea

• Mostly viral in origin—

No antibiotic required.

Only fluid & electrolite replacement.

•Bacterial origin---mostly campylobacter species

Rx– erythromycin or ciprofloxacin.

• Travellers diarrhoea:

E.coli common.

Rx—no antibiotic required.

Only fluid & electrolite replacement

*OCTREOTIDES

•Octreotides :synthetic analogue of somatostatin.

•Role in GIT:

It enhances Intestinal fluid secretion.

slows GIT motility in high doses.

•Use:

after vagotomy.

AIDS .

•Disadvantages:

steatorrhoea leads to deficiency of fat soluble vitamins.

Alteration of GIT motility causes nausea,

abdominal pain,flatulence.

•THANK YOU