Self Care Constipation

Bulk-Forming Laxatives

Include those products that contain methylcellulose (Citrucel®),

polycarbophil (Fibercon®), and psyllium (Metamucil®)

ii. Recommended choice as initial therapy for most forms of

constipation

Bulk-Forming Laxatives

i. Include those products that contain methylcellulose (Citrucel®),

polycarbophil (Fibercon®), and psyllium (Metamucil®)

Closely mimic the physiologic evacuation process

iii. 7-day use limitation does not apply

to this class because often they are used for preventive purposes

iv. MOA: dissolve or swell in the intestinal fluid, thereby forming gels

that facilitate passage of the intestinal contents

v. Onset of Action: may be delayed as long as 72 hr

Bulk-Forming Laxatives Warnings

Obstruction/choking could occur if appropriate fluid intake is not

maintained

1. NOT appropriate for patients who must restrict their fluid intake (heart failure)

vii. Common adverse effects include abdominal cramping and

flatulence

1. Not systemically absorbed

viii. Not recommended for children < 6 years except under advice of a

health care provider

ix. Choose sugar-free agents if diabetic or carb/calorie restricted diet

Hyperosmotics

Include polyethylene glycol 3350 (PEG 3350/Miralax®) and

glycerin

MOA: contain large, poorly absorbed ions that draw water into

the colon or rectum to stimulate a bowel movement

PEG 3350/Miralax®

powder 17 g per capful in 4-8 ounces of

beverage daily in adults > 17 years

1. Produces bowel movement within 12-72 hrs

2. Very little absorbed systemically; few side effects and no

significant drug interactions

Glycerin is available a

rectal suppositories to produce a bowel

movement within 15-30 minutes

1. Safe for occasional use in all age groups

Emollients(Stool Softeners)

Includes both docusate sodium (Colace®) and docusate calcium

1. Sodium’s availability in multiple strengths and dosage

forms results in more frequent use

ii. MOA: they increase the wetting efficiency of intestinal fluid and

facilitate a mixture of aqueous and fatty substances to soften the fecal mass

Emollients(Stool Softeners) side effects & action

Onset of Action: 12 to 72 hours (usually achieved within 48 hrs)

iv. Generally well tolerated, with little to no side effects or drug

interactions; Used in ages > 2 y/o

v. Frequently used along with a stimulant (senna or bisacody)

as a long-term treatment for opiate-induced constipation

40% of pain patients experience this adverse effect

2. Tolerance does NOT develop; dependent on opioid dose

and duration of use

Stimulants

Includes senna or sennosides (Ex-lax®, Senokot®), bisacodyl

(Dulcolax®), and castor oil

Stimulants MOA

increase intestinal motility by local irritation of the mucosa

or smooth muscle; also secretes water and electrolytes in the

intestine

Stimulants Onset Action

6-10 hours but may require 24 hours;

suppositories take effect 15-60 min

Stimulants Adverse effects

include severe cramping, electrolyte/fluid

deficiencies, and hypokalemia; in some people excessive

evacuation of fluid at excess doses

v. subject to overuse (anorexia, bulimia)

Stimulants combination products

Combination products that include both senna/sennosides and

docusate include Senna-S®, Senokot-S®, and Peri-Colace

Saline Agents

Includes magnesium hydroxide (Phillips® Milk of Magnesia),

magnesium citrate, and sodium phosphate (Fleet Phospho-Soda

Saline Agents MOA

draws water into the intestine, causing an increase in

intraluminal pressure and motility

iii. Also used for acute bowl evacuation

before a procedure (colonoscopy)

Saline Agents Onset Action

30 minutes to 6 hours for oral doses and

between 2 and 15 minutes for rectal doses

Saline Agents Warnings, Adverse effects

Can cause serious electrolyte imbalances

if used long term or at higher-than-recommended doses

1. Hypermagnesemia, hyperphosphatemia

 Avoid in older adults and patients with renal

impairment or heart failure

vi. Adverse effects include:

1. Abdominal cramping; nausea/vomiting

2. dehydration

 Patients who cannot tolerate fluid loss should not

use saline agents

 Take doses with water to prevent dehydration

Lubricants (Mineral Oil) MOA

soften fecal contents by coating the stool, thus preventing

absorption of fecal water

Lubricants (Mineral Oil) Onset Action

6 to 8 hours after oral administration and 5 to 15

minutes after rectal administration

Lubricants (Mineral Oil) don’t recommend

Available as a liquid for oral or rectal administration

iv. Because of safer agents, its use in self-care is strongly

DISCOURAGED

v. Excessive dosage increases the possibility of loss of fat-soluble

nutrients (vitamins A, D, E, and K) from the GI tract and enhances

the likelihood of product aspiration

(must take mineral oil in the upright position)

vi. Avoid in patients taking anticoagulants (warfarin), bedridden

patients, or in individuals with swallowing difficulties

Product Selection Guidelines

Recommend a product with the lowest likelihood of adverse effects

i. bulk-forming closely duplicates the

normal physiologic process however may take 72 hours or longer

ii. PEG 3350/ MiraLAX has the strongest support for efficacy and

safety; based upon clinical evidence supporting its effectiveness

1. If unable to produce response, a stimulant should be

considered

Ages 2 to younger than 6:

docusate sodium or magnesium hydroxide

. For faster relief, pediatric

glycerin suppositories. Oral senna when all other

treatments have failed.

Ages 6 to younger than 12

bulk-forming agents, docusate

sodium, or magnesium hydroxide. Glycerin suppositories

or oral stimulants when other treatments have failed.

Advanced Age

v. bulk-forming laxatives can be considered 1st step

1. Sugar-free products = diabetic patients

2. Dehydrated, frail, bedridden, or patients unable to drink

fluids should avoid

vi. PEG 3350/ MiraLAX can also be considered 1st line

vii. Stool softeners (docusate) may be helpful especially with painful

defecation (hemorrhoids)

viii. AVOID: mineral oil, saline laxatives, and stimulants (shifts in fluid and electrolytes)

Pregnancy

dietary measures should be

attempted as an initial measure in most patients

ii. bulk-forming laxatives are the

common first-line choice because of their safety and effectiveness

iii. Some prenatal vitamins have docusate sodium included in the

tablet

iv. If needed, short term use of senna or bisacodyl is considered low

risk in pregnancy

1. Some experts consider PEG 3350 to be a 1st line choice but

more data are available for stimulants

Bulk-forming laxatives and PEG 3350 are 1st line choices in most adults

(take 72 hours to work)

glycerin suppositories or stimulant laxatives

provide faster relief

Most common adverse effects of laxatives are abdominal cramping, gas,

bloating, or diarrhea