GI system 2: Laxatives Flashcards
A pt is being prepared for a colonoscopy. The nurse expects which laxative to be used as preparation for this procedure?
A) methyl cellulose (bulk forming laxative)
B) docusate sodium (colace)
C) PEG 3350 (lax a day)
D) glycerin
C
When a nurse teaches a pt about taking bisacodyl tablets, which instruction is correct?
A) take this medication on an empty stomach
B) chew the tablet for quicker onset of action
C) take this medication with juice or milk
D) take this medication with an antacid if it upsets your stomach
A
A patient has been given PEG 3350 (lax a day) as preparation for à colonoscopy. He began to have diarrhea after about 45min. Two hours later, he tells the nurse that the diarrhea has not stopped yet. What should the nurse do?
A) give him an anti diarrheal
B) give him another dose of PEG 3350 (lax a day)
C) remind him that it may take up to 4hrs to reach therapeutic results
D) report this to the doctor
C
Diarrhea is normal within 30-60min after taking PEG.
Takes 4hr to completely cleanse the bowel
True or false, a laxative can be given at the same time as a person’s morning medications?
False, it will affect the absorption of the other medications
True or false, a pt with renal insufficiency should be counselled to take milk of magnesia for relief of constipation?
False, it will further affect the kidneys, contraindicated with renal insufficiency
True or false, mineral oil can affect the absorption of Vitamin D?
True
True or false, psyllium is the laxative of choice for an elderly pt on a fluid restriction?
False, needs to be taken with lots of water to prevent esophageal obstruction and fecal impaction
A 48 yrs old pt who has been admitted for abdominal pain has not had a BM in 4 days. The pt’s abdomen is distended and slightly tender. Which laxative would be appropriate for this patient?
A) Milk of magnesia
B) a bulk forming laxative (psyllium)
C) mineral oil
D) no laxatives should be given at this time
D
Thèse laxatives are contraindicated in the presence of undiagnosed abdominal pain because taking a laxative in cases of intestinal obstruction could be harmful to the pt.
No laxatives should be given in the presence of undiagnosed abdominal pain
Which medication is considered a bulk forming laxative?
Psyllium hydrophilic (Metamucil)
What is psyllium used for?
- acute and chronic constipation
- IBS, diverticulosis
How does psyllium (Metamucil) the bulk forming laxative work?
Works by :
- absorbs water and increase bulk stimulating peristalsis
= bowel distension = initiation of reflex bowel activity
What are some AE associated with psyllium (Metamucil)?
- electrolytes imbalances
- gas formation
- esophageal blockage
- fluid overload
What are some contraindications with the use of psyllium (Metamucil), docusate sodium (colace) and polyethylene glycol (lax a day / PEG 3350)
- KDA
Caution use with:
- eating disorder
- acute surgical abdomen
- appendicitis symptoms
- fecal impaction
- intestinal obstruction
- undiagnosed abdominal pain
What are some drug interactions with psyllium (Metamucil)?
- decrease absorption with : antibiotics, digoxin, salicylates, tetracyclines, warfarin
How should psyllium (Metamucil) the bulk forming laxative be taken? And why?
- should be taken with a high increase in fluid to prevent esophageal and bowel obstruction
- powder mixed in water
With lots of water bc — Metamucil mixed with water forms a sort of gel that can create a small obstruction
What are some nursing assessments to be done and in what order in terms of the GI?
- full GI assessment
- pattern of BM
1. inspection
2. bowel sounds
3. Percussion
4. Palpation - long term use of laxatives
- assess VS, daily weights, I&O
- fluid and electrolyte levels
- diet
For all laxatives and antidiarrheals
Which laxative is considered emollient or stool softener?
And which is considered lubricant laxative?
Emollient:
- docusate sodium (colace)
Lubricant:
- mineral oil
What are docusate sodium and mineral oil indicated for?
Prevention of constipation in pts who should avoid straining (post MI, rectal surgery)
What is the mechanism of action of the stool softener docusate sodium (colace)?
- promotes more water and fat in the stools
- allows bowel to soften and expand stool to promote bowel distension and peristaltic action
What is the mechanism of action of mineral oil, the lubricant laxative?
- lubricates fecal material and intestinal walls and prevents water from leaving the bowel
- does not stimulate
What are some AE with docusate sodium and mineral oil?
Docusate sodium:
- skin rashes
- electrolyte imbalances
- lipid pneumonia
Mineral oil:
- decreased absorption of vitamins (A, D, E, K)
How should docusate sodium (colace) be taken?
- Should be taken with at least 180mls of water
And an increase of 1800 to 2400 mls of water per day
Which medication is considered hyper osmotic laxative?
Polyethylene glycol (Lax-a-day/PEG 3350)
What is the mechanism of action of polyethylene glycol?
- increased fecal water content = increase distension
- increase peristalsis
- increase evacuation
Works on the large intestine only
Which laxative is usually used for diagnostic and surgical procedure (for bowel prep)?
Polyethylene glycol (lax a day)
Bc it has a very quick onset (30-60min)
Takes about 4hrs for complete cleansing of the bowel
What are AE of polyethylene glycol (lax-a-day)?
- abdominal bloating
- electrolyte imbalances
- rectal irritation
What are drug interactions with polyethylene glycol (lax a day)?
- increase CNS dépression: barbiturates, anaesthetic, opioids, and antipsychotic
Which laxative is considered a saline laxative?
Magnesium chloride (milk of magnesia)
What is the mechanism of action of magnesium chloride ?
- works by increasing osmotic pressure in small intestines by decreasing water absorption and increase water and electrolytes secretion into Bowel lumen
= watery stool - increase distension = increase peristalsis & evacuation
What are the contraindications with magnesium chloride?
And it’s cautions?
- KDA
- pt with kidney Insufficiency
- eating disorder
Caution:
- with older adults (increased risk of dehydration and electrolyte imbalances)
- acute surgical abdomen
- abdominal pain
- appendicitis
- intestinal obstruction
- fecal bleeding
- n&v
What are some AE with magnesium chloride?
- magnesium toxicity (w/ renal insufficiency)
- electrolyte imbalances
- cramping
- increased thirst
- diarrhea
How should magnesium chloride be taken?
Should be taken with a good intake of fluids
Which laxative is considered stimulant ?
Bisacodyl (dulcolax)
Which three laxatives are also used prior to diagnostic and surgical procedures?
- bisacodyl (dulcolax)
- magnesium chloride (MOM)
- polyethylene glycol (Lax-A-Day)
How should bisacodyl (dulcolax) the stimulant laxative be taken?
- take on an empty stomach for faster action
- pt should not consume milk, antacids, or juices with dose or within 1hr of taking the medication
- if per rectum: pt should lay on left side for 15-30 min for med to dissolve
- need large amount of laxative to produce BM
Caution bc: can lead to dependency
What are the AE associated with bisacodyl (dulcolax)?
- electrolyte imbalances
- stretched/lazy colon, IBS
- gastric irritation
- discoloured urine
- skin rashes
- nutrient malabsorption
- rectal irritation
What are some drug interactions with bisacodyl (dulcolax)?
- decrease absorption of : antibiotics, digoxin, nitrofurantoin, tetracycline, oral anticoagulants
What are the caution and contraindications with bisacosyl (dulcolax)?
- KDA
- eating disorder
Caution use:
- acute surgical abdomen
- n&v
- appendicitis
- fecal impaction
- intestinal obstruction
What is the prototype medication of antiflatulent medication?
Simethicone (Ovol)
What is simethicone (ovol) used for?
- diverticulitis
- dyspepsia
- peptic ulcer
- spastic or irritable colon
- reduce discomfort of gastric/intestinal gas and helps release (by mouth or rectum)
When and how should simethicone (ovol)?
- should be taken after meals and at bedtime
- avoid problematic foods (spicy, gas forming foods: beans, apples, fibres, carbonated beverages))
