Browse Plus Oral Powder

Dosage

Children: Refer to the BNF for Children for appropriate dosing information in paediatric cases, especially in instances of overdose.

Adults: Refer to the BNF for specific dosing information based on clinical circumstances, particularly in cases of overdose.

Mechanism of action

Ethylene glycol is metabolized by alcohol dehydrogenase to glycoaldehyde, which is subsequently converted to glycolic, glyoxylic, and oxalic acids. These metabolites contribute to anion gap metabolic acidosis and are responsible for tissue injury through the formation of insoluble calcium oxalate crystals.

Pharmacodynamics

The toxicity of ethylene glycol arises from its metabolites, particularly glycolic and oxalic acids. These compounds induce metabolic acidosis, lead to renal failure through calcium oxalate crystal deposition in the kidneys, and can cause neurological impairment. The anion gap increases due to the accumulation of these acids, leading to complications such as cardiovascular instability and potential multi-organ failure.

Pharmacokinetics

Ethylene glycol is rapidly absorbed after oral ingestion. It undergoes first-pass metabolism primarily in the liver, where it is converted into its toxic metabolites. The elimination half-life of ethylene glycol varies but is generally prolonged in cases of renal impairment. Renal excretion of metabolites contributes to the duration of toxicity, necessitating prompt medical intervention in cases of overdose.

Adverse effects

• Metabolic acidosis
• Renal failure
• CNS depression
• Hypocalcemia
• Cardiovascular collapse
• Pulmonary edema

Precautions

• Use with caution in patients with renal impairment
• Monitor for signs of metabolic acidosis
• Evaluate electrolyte levels, particularly calcium

Pregnancy

There is limited data on the safety of ethylene glycol in pregnancy. It should only be used if clearly needed.

Breast-feeding

It is unknown if ethylene glycol is excreted in human milk. Caution is advised.

Storage

Store in a tightly closed container at room temperature, away from heat and moisture.

Formulations

• Liquid

Indications

• Constipation
• Bowel preparation prior to colonoscopy or other gastrointestinal procedures

Dosage

Children: Refer to specific clinical guidelines for dosing in children, as it may vary based on age and weight.

Adults: Refer to specific clinical guidelines for dosing based on the condition being treated, as it may vary.

Mechanism of action

Polyethylene glycol acts as an osmotic agent in the gastrointestinal tract. It draws water into the lumen of the intestines, which increases the water content of the stool. This action helps to soften the stool and stimulate bowel movements, making it effective for treating constipation.

Pharmacodynamics

The pharmacodynamic effects of polyethylene glycol include its ability to increase the frequency of bowel movements and improve stool consistency. Its osmotic properties allow it to enhance water retention in the stool, leading to a larger volume of fecal matter and facilitating easier passage through the intestines.

Pharmacokinetics

Polyethylene glycol is poorly absorbed from the gastrointestinal tract, which is beneficial for its use as a laxative. It is primarily excreted unchanged in the feces. The onset of action typically occurs within 24 to 72 hours after ingestion, depending on the dosage and individual response.

Contra-indications

• Hypersensitivity to polyethylene glycol or any component of the formulation
• Bowel obstruction
• Gastrointestinal perforation
• Severe inflammatory bowel disease (such as Crohn's disease or ulcerative colitis)

Adverse effects

• Nausea
• Abdominal cramping
• Diarrhea
• Bloating
• Electrolyte imbalances
• Dehydration

Interactions

• May interact with medications that affect electrolyte levels
• May affect the absorption of other oral medications due to altered gastrointestinal transit time

Precautions

• Use with caution in patients with renal impairment
• Monitor for signs of dehydration or electrolyte imbalance, particularly in elderly patients or those with comorbidities

Pregnancy

Polyethylene glycol is generally considered safe in pregnancy, although it is advisable to use it under medical supervision.

Breast-feeding

Polyethylene glycol is considered safe during breastfeeding, as it is poorly absorbed and unlikely to affect breast milk.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Powder for oral solution
• Liquid formulation

Mechanism of action

Ethylene glycol is metabolized by alcohol dehydrogenase to glycoaldehyde, which is then metabolized to glycolic, glyoxylic, and oxalic acids. These acids, along with excess lactic acid are responsible for the anion gap metabolic acidosis. Oxalic acid readily precipitates with calcium to form insoluble calcium oxalate crystals. Tissue injury is caused by widespread deposition of oxalate crystals and the toxic effects of glycolic and glyoxylic acids.