The same medicine at the same dose behaves differently at 75 than at 35. Kidneys and liver clear medicines more slowly, body composition changes how they distribute, and the brain is more sensitive to anything sedating. Add the fact that older adults typically take more medicines, and both side effects and interactions become more likely.
The most useful idea on this page: new symptoms in an older person are frequently attributed to ageing when they are caused by medicines. Confusion, unsteadiness, tiredness, constipation, dizziness and low mood are all common side effects and all easily explained away as simply getting older. If any of these are new, the medicine list is worth reviewing before accepting them.
Common side effects during long-term use
The groups causing most avoidable harm in older adults:
- Anti-inflammatories. Stomach bleeding, often without warning indigestion, plus kidney effects and worsening heart failure. See NSAID side effects.
- Sedatives and sleeping tablets. Falls, fractures, confusion and memory problems. See sleeping tablet side effects.
- Sedating antihistamines, including those in night-time remedies, which add dry mouth, constipation and urinary difficulty.
- Blood pressure medicines, where dizziness on standing raises fall risk.
- Blood thinners, where bleeding risk is higher and falls matter more.
A pattern worth naming: several medicines each with a mild drying and sedating effect combine into something that looks like cognitive decline. That total is often reducible.
Serious or persistent symptoms to discuss with a clinician
Emergency care for vomiting blood or black tarry stools, a fall with a head injury particularly on a blood thinner, sudden confusion, chest pain, or difficulty breathing.
Same day for new unsteadiness or drowsiness, passing much less urine than usual, being unable to pass urine at all, marked ankle swelling, or a new fall.
Treat a fall as a medicine question as well as a mobility one. Falls are among the clearest signals that a medicine list needs reviewing.
Dose changes, missed doses and monitoring tests
Ask for a medicines review. This is a structured look at everything being taken, asking of each item whether it is still needed, still at the right dose, and still worth its side effects. Needs change over years, and medicines started long ago sometimes continue by momentum rather than by decision.
Bring everything to the review, including supplements and anything bought over the counter. Kidney function is worth knowing, since it determines appropriate doses for a number of common medicines.
Deliberately reducing or stopping medicines that are no longer helping is a recognised part of good care, not a withdrawal of treatment. It is done gradually and with monitoring.
Interactions with OTC medicines and supplements
Interaction risk rises with the number of products taken, and pharmacy purchases are the part most often missing from the record. See OTC medicines in older adults and supplement and medicine interactions.
During illness with vomiting or diarrhoea, dehydration combined with certain medicines is a recognised route to kidney injury. Ask for sick day advice in advance.
What to ask your doctor before changing treatment
- Can we review everything I take, including what I buy myself?
- Is anything on this list still needed, or still at the right dose?
- Could any of these be causing my tiredness, unsteadiness or confusion?
- Which of these raise my risk of falling?
- When was my kidney function last checked?
Related chronic medication guides
- Chronic medication side effects
- Should I stop my chronic medication
- OTC medicines with chronic medication
- Medication side effects hub
- Report a side effect in South Africa
See also mental health medication in older adults.
Medical Disclaimer: This content is for informational and educational purposes only and does not constitute medical diagnosis, prescription, or professional advice. Always read the patient information leaflet and consult a qualified doctor or pharmacist regarding any medicine or health concern.