Low Adherence Rate with Polyethylene Glycol

The sentiment of wanting to get their kid off laxatives/stool softeners is frequently expressed at GI visits.  I certainly understand this.  Though, if a child is not stooling adequately when these medicines are withheld, this is usually detrimental for the child.

Given the frequency of this sentiment, it is not surprising that a recent study (IJN Koppen et al. J Pediatr 2018; 199: 132-9) reports low adherence with polyethylene glycol treatment in children with functional constipation.

In this cross-sectional survey using the Medication Adherence Report Scale (MARS-5), with scores of ≥23 indicating better adherence, the authors found that only 43 of 115 (37%) children were adherent.  The authors note that one of the determinants of adherence was treatment convenience.

The MARS-5 does not objectively measure the exact intake of medication; thus, the exact rate of adherence is unclear.  In addition, there is likely to wide variation in adherence among different populations.

My take: this study shows, at least in some populations, a low adherence with constipation therapy.  Sticking with treatment, for constipation and every other condition, usually results in better outcomes.

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If someone is not taking their medication, perhaps this cereal would help. (I am not officially endorsing this product, but think the name is funny.)

One Day Polyethylene Glycol 3350 Prep

A recent study (B Sahn et al. JPGN 2016; 63: 19-24) with 155 patients prospectively showed that a 1-day polyethylene glycol (PEG) 3350 prep was safe and fairly effective.

The prep: 4 g/kg PEG in children with weights 10-50 kg and (with 238 gm for those >50 kg along with a single dose of a stimulant: either bisacodyl 5 mg-15 mg orally (10 mg for 21-30 kg) or senna (17.6 mg for 20 kg, 26.4 mg for 21-30 kg, and 52.8 mg for >31 kg).  The PEG was mixed typically with a sports drink to a max of 64 oz.

Key findings:

  • Hypokalemia was noted in 37 (24%) but none lower than 3.3 mmil/L.
  • Hypoglycemia was identified in 5 (3 were younger than 7). The one patient with severe hypoglycemia (31 mg/dL) was a one-year-old with corticosteroid dependency and had missed his morning steroid dose.
  • Colon cleansing was excellent or good in 77%.  The authors note that this suboptimal cleansing is due in part to the difficulty of using split-dosing in pediatrics.
  • 3/4ths of patients found the prep to be easy or average to tolerate.

My take: This study validates the common approach of using 1-day PEG 3350 preps in children.  Due to the low risk of hypoglycemia, particularly in young children, and the frequent mild hypokalemia, some children may benefit from starting intravenous fluids prior to induction of anesthesia.

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Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications/diets (along with potential adverse effects) should be confirmed by prescribing physician/nutritionist.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

Arthur Ravenel Jr Bridge

Arthur Ravenel Jr Bridge


Data Supporting Miralax

A summary of the effectiveness of polyethylene glycol for chronic constipation, fecal disimpaction, and as a bowel preparation are presented in a recent article (JPGN 2013; 57: 134-40).

The article provides information on the biochemistry and mechanism of action along with a good number of references –49.

From the summary:

“PEG is an osmotic laxative used in children in the last few years.  It is more effective than lactulose for the treatment of chronic constipation.  It is equally effective compared with milk of magnesia and mineral oil for the long-term treatment of constipation but has a much better acceptance rate…It is a safe medication without any significant adverse effects.  Because PEG can be mixed in a beverage of the patient’s choice, it has excellent long-term patient acceptance.”

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