QUESTION 1
Based on the information above, what is the minimum expected amount of sorbitol (in g) for an adult that could produce a laxative effect?
- 70% = 70 g/100 ml = 7 g/10 ml = 21 g/30 ml
QUESTION 2
Assuming the dose from Q1 is effective for a 70 kg adult, calculate a dose, in g/kg, that could be extrapolated for use in patients of different sizes.
- For a 70 kg patient: 21 g/70 kg = minimum effective dose = 21 g/70 kg = 0.3 g/kg
QUESTION 3
What is the daily dose of each polyol that a 2-year-old boy would receive if treated with Clarityn syrup?
- Sorbitol = 140 mg/ml x 5 ml = 700 mg
- Maltitol = 600 mg/ml x 5 ml = 3000 mg
QUESTION 4
If the 2 year old weighs 12 kg what is the dose per kg of each polyol?
- Sorbitol = 700 mg / 12 kg = 58 mg/kg
- Maltitol = 3000 mg / 12 kg = 250 mg/kg
QUESTION 5
What proportion of the usually pharmacologically effective dose of each polyol will this child receive?
- Sorbitol dose = 58 mg/kg
- Minimum sorbitol dose for effect = 170 mg/kg (as the child is male)
- Proportion of effective dose = 58 mg/kg / 170 mg/kg = 34%
- Sorbitol dose = 250 mg/kg
- Minimum sorbitol dose for effect = 800 mg/kg
- Proportion of effective dose = 250 mg/kg / 800 mg/kg = 31%
- Both of these doses (individually) are less than the expected thresholds to cause an effect, but together, and in combination with other medicines or foods, may be enough to cause effects, particularly in sensitive individuals