Dr.Arul AmuthanMMMC, Manipal

Antiemetics, laxatives, antidiarrhoeals

Antiemetic agents

What is vomiting? Causes?

Morning sickness, motion sickness….

These are drugs which prevent or stop vomiting

Examples for antiemetic agents

Ondansetron, granisetron

Metoclopramide, domperidone

Hyoscine (scopolamine), promethazine

Uses of antiemetic agents

Cancer chemotherapy induced vomiting - ondansetron

Motion sickness – hyoscine

Morning sickness – cyclizine

Post operative vomiting - promethazine

Levodopa induced vomiting - domperidone

Gastro esophageal reflux disease - metoclopramide

Adverse effects of antiemetic agents

Metoclopramide: blockade of D2 receptors in basal

ganglia leads to drowsiness, restlessness, parkinsonism

like symptoms

Metaclopramide – gynaecomastia, galactorrhoea

Diarrhoea, abdominal cramps

Cisapride – ventricular arrhythmia

Antidiarrhoeals

What is diarrhea? Causes?

Infective and non-infective diarrheas

How diarrhea happens ? [↑ motility and ↑ secretion]

These drugs are useful to control non infective diarrheas.

Sulfasalazine, mesalazine – (antisecretory)

Codeine, loperamide, diphenoxylate-atropine –

(antimotility)

Exmples for antidiarrhoeals

Noninfective diarrhoea

Mild travellers diarrhoea

Idiopathic diarrhoea in AIDS

Ulcerative colitis (there is more GIT secretion)

After anal surgery to induce constipation for short period

Uses of antidiarrhoeals

Laxatives

What is constipation? Causes?

How does it occurs?

These drugs stimulate GIT and causes excess defecation

Purgative

Examples for laxatives

Ispaghula, liquid paraffin, castor oil

Bisacodyl, senna

Magnesium sulfate, lactulose

Uses of laxatives

Functional constipation – less fiber food, less exercise,

tension behavior

Bedridden patients – old age, disability - to prevent and

treatment

To avoid straining at stools in hernia, eye surgery, piles, anal

surgery etc.

Preparation of bowel before surgery/delivery/abdominal

X ray/colonoscopy.

After anthelmintic therapy/ food poisoning – to flush out.