Due to advanced age, the elderly require different therapeutic strategies for pain . These strategies are due to a greater extent to metabolism and sensitivity due to age, concomitant diseases, the need for polymedication, high risk of adverse effects and drug interactions.
Among the relevant physiological aspects that modify the pharmacology of analgesics in the elderly are:
- Decrease in the absorption of oral medications. - Decrease in plasma proteins that bind drugs. - The volume of distribution of hydrophilic drugs decreases (lower level of water in the body). - The volume of distribution of lipophilic drugs increases (due to the increase in body fat). - Decrease in hepatic metabolism. - Decrease in creatinine clearance. - Increased sensitivity to opioids.
(Source: "Practical management of analgesics in the elderly", Revista Iberoamericana del dolor, N ° 4, 2007).