Lecture Laxatives, Diarrhea, IBD, IBS

Question 1

contraindications of laxatives

Answer 1

1. abdominal pain, nausea, cramps
2. acute surgical abdomen
3. fecal impaction / bowel obstruction
   (don’t give a laxative if you don’t know the cause bc this could cause rupture!)
4. habitual use
5. caution in pregnancy & lactation

Question 2

laxatives are classified base on ___.

Answer 2

on therapeutic effect (consistency of stool) and by type (group) of laxative

Therapeutic Effect (Table 79-3)

1. Group I - Watery stool in 2 – 6 hours
2. Group II - Semifluid stool in 6 – 12 hours
3. Group III - Soft stool in 1 – 3 days

Type (Table 79-2)

1. Bulk forming
2. Surfactant
3. Stimulant
4. Osmotic
5. Chloride channel activator
6. Misc

Question 3

Bulk forming laxatives

Answer 3

Psyllium [Metamucil]
methylcellulose [Citrucel]
polycarbophil [FiberCon]

Function like dietary fiber- swell with water, forms a gel that softens & increases fecal mass

Safest laxative, rarely produces adverse effects

Serious adverse effects
With insufficient water, psyllium may swell in the esophagus and cause obstruction.

Contraindications/precautions
Undiagnosed abdominal pain
Suspected intestinal obstruction
Fecal impaction

Nursing 101: Mix powder and granules with at least 8 ounces of a pleasant-tasting liquid immediately before use

Question 4

Surfactant laxative

Answer 4

docusate sodium [Colace]

Lowers surface tension of stool, allowing more water penetration – softens stool.
May also increase secretion and decrease absorption of water & electrolytes in intestine

Take with full glass of H2O
Soft stool in 1 – 3 days

Question 5

Stimulant laxatives

Answer 5

bisacodyl [Dulcolax, Correctal]
senna
castor oil

Stimulate intestinal motility
Increase secretion and decrease absorption of water & electrolytes in intestine

MOST are Group II
semifluid stool in 6-12 hrs
WIDELY used & abused by public
Used for constipation: opioid-induced and slow intestinal transit

bisacodyl [Dulcolax, Correctal]
oral 6-12 hrs
rectal 15-60 min
may cause burning/proctitis

senna [Senokot, Ex-Lax]
plant derived
may cause harmless yellow-brown or pink color of urine
turns colon a dark color

castor oil
2-6 hrs (Group I)
unpleasant taste
mix with fruit juice

Question 6

osmotic laxatives

Answer 6

laxative salts (magnesium hydroxide/citrate/sulfate, sodium phosphate)
polyethylene glycol [Miralax]
Lactulose

Question 7

laxative salts

Answer 7

magnesium hydroxide/citrate/sulfate,
sodium phosphate

poorly absorbed salts
osmotic action draws water into intestine
fecal mass softens, swells, stretches intestinal wall, stimulates peristalsis
6 – 12 hrs – low dose
2 – 6 hrs – high dose

AE:
Substantial water loss so increase water intake
renal impairment - Mg toxicity
Sodium- fluid retention (heart failure, HTN, edema), renal failure

Question 8

What is very useful as an enema in fecal impaction?

Answer 8

mineral oil

May cause:
lipid pneumonia
anal leakage
mineral oil in liver

Question 9

What is used to soften and lubricate impacted feces, and may stimulate rectal contraction? (It’s often used in infants with constipation)

Answer 9

glycerin suppository

30 min

Question 10

chloride channel activator (laxative)

Answer 10

lubiprostone [Amitiza]

~24 hours

Uses:
chronic constipation
IBS-C in women >18
opioid-induced constipation

Question 11

What is used as bowel prep?

Answer 11

sodium phosphate

polyethylene glycol-electrolyte [GoLYTELY]

Question 12

__ are the most effective antidiarrheals.

Answer 12

Opioids – because they slow peristalsis

Most common opioids
diphenoxylate [Lomotil]
loperamide [Imodium]

Question 13

NEVER use antidiarrheal to treat diarrhea caused by __.

Answer 13

poisoning or infection by toxin-producing organisms – let them OUT!

Question 14

Inflammatory Bowel Disease (IBD)

Answer 14

IBD is characterized by intestinal inflammation and is an exaggerated immune response

Crohn’s disease - Occurs anywhere in the GI tract; affects the Mucosal layer

Ulcerative colitis - Starts in the rectum and moves up

This is NOT IBS!!

Question 15

Treatment for IBD

Answer 15

No cure – control disease process

IBD treated with 5 types of drugs

1. 5-aminosalicylates (5-ASA) -(sulfasalazine)
2. Glucocorticoids (prednisone)
3. Immunosuppressants (azathioprine)
4. Immunomodulators (infliximab)
5. Antibiotics (metronidazole)

Question 16

“-alamine”, “-alazine”

Sulfasalazine [Azulfidine]
Mesalamine [Asacol, Pentasa], [Canasa, Rowasa]
Olsalazine [Dipentum]
Balsalazide [Colasal]

Answer 16

5-aminosalicylates (5-ASA)
Reduces inflammation in IBD

Most effective in mild to moderate UC (ulcerative colitis)

AEs

1. nausea, fever, rash, arthralgia
2. hematologic disorders
3. photosensitivity

Interactions

1. inhibits absorption of folic acid
2. warfarin – increases anticoagulant effect

Question 17

Thiopurines - Azathioprine, Mercaptopurine
Cyclosporine
Methotrexate

Answer 17

Immunosuppressants used to treat IBD

Long-term therapy: Induce/maintain remission
CD (Crohn’s) & UC (Ulcerative Colitis)

AEs

1. Pancreatitis
2. Neutropenia

Question 18

Infliximab
certolizumab pegol
adalimumab
natalizumab
vedolizumab
golimumab
ustekinumab

Answer 18

Immunomodulators used to treat IBD

monoclonal antibodies- modulate immune response
moderate to severe CD & UC

AEs

1. Infusion/injection site reactions
2. Infections - TB, Opportunistic
3. increased risk of lymphoma

Question 19

Irritable Bowel Syndrome (IBS)

Answer 19

Most common disorder of GI tract
20% Americans, W>M

Characterized by cramping abdominal pain (may be severe) that cannot be explained by structural or chemical abnormalities

symptoms have been present for 12 weeks over the past year
diagnosis of exclusion

May occur with diarrhea (IBS-D), constipation (IBS-C), or both (IBS-M)

4 types of drugs historically used

1. antispasmodics (hyoscyamine & dicyclomine)
2. bulk-forming agents
3. antidiarrheals
4. tricyclic antidepressants - because depression is common r/t illness and chem imbalances in the body