Prescribing in Old Age

Question 1

Describe how pharmacokinetics of drugs changes in old age?

Answer 1

In older people there is less acidic gastric pH so acidic drugs are absorbed less and basic drugs are absorbed more
Old people are more likely to suffer from opioid toxicity because they absorb more of basic drugs
They have lower levels of some proteins meaning more free drugs of certain types can circulate
Reduced renal and hepatic function which occurs in old age should be taken into account when prescribing

Question 2

Polypharmacy is generally thought of as _____

Answer 2

> 4 medications

Question 3

What is meant by the anti-cholinergic burden?

Answer 3

cumulative effect of taking one or more medications with anti-cholinergic activity (note that quite a lot of drugs have anti-cholinergic activity but aren’t classed as anticholinergics)

Question 4

Explain what a prescribing cascade is and why it is important to avoid?

Answer 4

When you end up in a spiral of prescribing for side effects of drugs when the person didn’t need the original drug that badly in the first place.
Important to avoid to decrease morbidity and side effects that could seriously effect health.

Question 5

Explain what number needed to treat and number needed to harm is?

Answer 5

The Number Needed to Treat (NNT) is the number of patients you need to treat to prevent one additional bad outcome (death, stroke, etc.)

Number needed to harm (NNH) is an indicates how many persons on average need to be exposed to a risk factor over a specific period to cause harm in an average of one person who would not otherwise have been harmed.

So presumably if NNH is low but NNT is high then more people are going to do badly on that drug!