Pharmacology Flashcards
What determines the absorption of oral medication
Gastric acid secretion
Gastric motility
How is the absorption of oral medication different in children
In young infants, gastric emptying is prolonged until 6 months
Gastric acid output does not reach adult values until 3rd year of life
slower absorption
How is the absorption of oral medication different in children
In young infants, gastric emptying is prolonged until 6 months
Gastric acid output does not reach adult values until 3rd year of life
slower absorption
Which health conditions can affect the absorption of oral medication in children
GORD
Biliary function
GI micro flora
How is the absorption of percutaneous medication different in children
Enhanced in children and infants due to skin fragility
e.g. topical steroids
What are the two factors that affect drug distribution
Body Composition
Plasma Protein
How does drug distribution differ in children
Extracellular fluid volume and total body water much higher in infants and children - require greater doses of water soluble drugs than adults on a weight-for-weight basis
Reduced protein binding in premature babies - higher concentrations of free (active) drug and higher apparent volumes of distribution
How is drug metabolism different in children
Enzyme systems have not fully developed
Hepatic function is greater than in adults due to comparative size of liver - need higher doses of some drugs
What is the drug route of choice in children
Oral where possible
Paediatric formulations must be used where available
What determines the rate of drug excretion
The renal excretion - GFR
Varies in ages
Dose is determined by it
How can drugs be given if the child uses an NG or PEG tube
Tablets or capsules may be opened, dissolved, suspended or crushed and delivered through the tube
Enteric coated or sustained release preparations cannot be used in this way
Why should medicines not be added to feeds
The dose is lost if feed not completed
List common reasons for non-compliance with paediatric drug treatment
Resistance of child taking medication - consider formulation, taste
Complicated dosing regime
Misunderstanding of instructions
Side effects
Drug dose calculations in children are usually based on what
Based on age, weight and/or surface area
For chronic treatment, doses should be re-evaluated regularly based on changing weight and age
The child dose should not exceed the standard adult dose - be wary with older/heavier children
Calculated drug doses for children can be rounded off to make measurement/administration easier - true or false
True
Must stay within 10% of dose
