SENNA

Question 1

what is the drug class?

Answer 1

laxative

Question 2

how does it work? (4)

Answer 2

• is a stimulant
• it increases water and electrolyte secretion from colonic mucosa
• this increases colonic content
• and stimulates peristalsis

Question 3

how does senna stimulate peristalsis? (4)

Answer 3

• senna is metabolised by bacteria in the intestine
• this produces metabolites
• these metabolites have a direct action on the enteric nervous system
• this stimulates peristalsis

Question 4

Indications

Answer 4

constipation

Question 5

Contra-indications (3)

Answer 5

• intestinal obstruction
• haemorrohoids
• anal fissures

Question 6

Side effects (3)

Answer 6

1. abdo pain
2. diarrhoea
3. melanosis coli

Question 7

What is melanosis coli?

Answer 7

reversible pigmentation of the intestinal wall

Question 8

interactions

Answer 8

none

Question 9

elimination

Answer 9

faeces or urine