Constipation Rx and Therapeutic Approach Flashcards
Methylnatrexone bromide (Relistor®)
how it works
onset
use
AE
Blocks mu-opioid receptors directly in GI tract
Onset: 30 – 60 min
Use: Opioid induced constipation (palliative care
patients) where insufficient response to the
other laxatives
Subcutaneous every other day
Adverse effects: diarrhea, abdominal pain,
flatulence, nausea, dizziness, hyperhidrosis
naloxegol (Movantik®)
how it works
use
Pegylated naloxone derivative
25 mg oral tablet daily on empty stomach
Indicated for opioid induced constipation not responding
to other laxatives
name 2 mu-receptor antagonists
Methylnatrexone bromide (Relistor®) naloxegol (Movantik®)
Prucalopride (Resotran®)
how it works
onset
use
AE
Highly selective 5-HT4 receptor agonist – increases GI
peristalsis – prokinetic action (agonist cause contractio)
Dose: 2 mg daily
Acts within 2 – 3 hours (quick, used chronically)
Use: indicated for female patients with severe
constipation who have not responded to other
laxatives (though studies in men have shown benefit)
Adverse effects: nausea, diarrhea, cramping
Discontinue if inadequate response within 4 weeks
Linaclotide (Constella®) – Guanylate Cyclase-C agonist - Rx
indication
Indications: Chronic idiopathic constipation and IBS with
constipation.
Therapeutic approach to acute
constipation
which pdts for mild?
which for moderate to severe for rapid response?
mod to severe for slower response?
Mild
Bulk forming laxative
Moderate to severe or wants rapid response:
Glycerin or bisacodyl supp
or
Magnesium hydroxide/citrate
or
Stimulant laxatives (ie senna, bisacodyl)
If rapid response not required then PEG or
lactulose can be considered
No relief consider sodium phosphate enema
Onset of Action – Targeting Laxatives
Glycerin supp
Bisacodyl supp
Enemas
15 – 60 minutes
Onset of Action – Targeting Laxatives Saline laxatives (ie magnesium products)
0.5 – 3 hours
Onset of Action – Targeting Laxatives Stimulant laxatives (senna, bisacodyl oral)
6 – 12 hours
Onset of Action – Targeting Laxatives
1-4 days?
Bulk forming laxatives (12 – 72h)
Emollient/stool softeners (12 – 72h)
Lactulose (24 – 48h)
PEG (48 – 96h)
what pharm would you recommend if there was not enough fibre intake?
bulk forming agent
what pharm would you recommend if there was enough fibre intake?
trial of osmotic laxative (PEG, lactulatose, mag sit) for 4-8 wk + fibre supplement
if not effective: glycerin supp, stimulant lax (bisacodyl), enema as rescue therapy
can try trial of linaclotide or prucalopride for 8-12 wk
refer fo futher assessment if not effective
Opioid induced constipation (Palliative care
patients)
which products are used
which are avoided
- Need to consider regular laxative use if on chronic opioids.
- Stimulant laxatives or osmotic laxative (PEG, lactulose) are often used.
- Docusate is sometimes included in regimens but there is little data available that it is effective; for example regimens:
- Sennokot 2 tabs at hs (or bid or tid) + Docusate 100 mg bid
- Avoid bulk forming laxatives – impaction
- Methylnatrexone or naloxegol – severe not responded to other laxatives
Elderly constipation
first line
pharm options
First line: fluid and fiber (diet or bulk forming laxatives)
Options: PEG, lactulose – evidence to support in elderly
Consider glycerin supp for quick action
Avoid magnesium laxatives if renal impairment
Stimulant laxatives – consider if above options fail,
concern of side effects (abdominal cramping, bloating,
diarrhea) in elderly
Pediatrics constipation Infants (<1 year old)
first line
pharm options
Assess if milk intolerance (can cause constipation)
Consider fruit with sorbitol (ie prune juice, apples, pear)
First line: glycerin supp
Options: lactulose or PEG
Avoid mineral oil, stimulants and enemas
