Medicine Use and Prescribing for the Elderly: Complete Guide with FAQs
Introduction
- Older adults often require medications to manage chronic conditions, but physiological changes with aging can affect drug metabolism and increase the risk of side effects.
- The goal is to use the fewest effective medications to achieve therapeutic goals while minimizing adverse effects.
- Common challenges include polypharmacy, drug interactions, and altered pharmacokinetics.
Key Considerations for Prescribing in the Elderly
1. Physiological Changes Affecting Drug Therapy
- Absorption: Generally unchanged, but conditions like reduced stomach acid may impact some medications (e.g., calcium carbonate).
- Distribution: Increased fat stores lead to prolonged half-life of fat-soluble drugs (e.g., benzodiazepines); reduced total body water affects water-soluble drugs (e.g., digoxin).
- Metabolism: Decreased liver metabolism (Phase I reactions) can prolong drug effects (e.g., opioids, benzodiazepines).
- Excretion: Decline in renal function reduces clearance of renally excreted drugs (e.g., aminoglycosides, NSAIDs).
2. Polypharmacy
- Defined as the use of five or more medications.
- Increases the risk of adverse drug reactions, drug-drug interactions, and non-adherence.
3. Medication Review
- Regularly evaluate the need, effectiveness, and safety of each medication.
- Use tools like the Beers Criteria and STOPP/START criteria to identify potentially inappropriate medications.
Common Conditions and Medicines for the Elderly
1. Hypertension
- Preferred Medicines:
- ACE inhibitors (e.g., lisinopril).
- Calcium channel blockers (e.g., amlodipine).
- Thiazide diuretics (e.g., hydrochlorothiazide).
- Avoid: Alpha-blockers and centrally acting drugs due to increased fall risk and sedation.
2. Diabetes
- Preferred Medicines:
- Metformin (if renal function allows).
- DPP-4 inhibitors (e.g., sitagliptin) due to lower risk of hypoglycemia.
- Avoid: Sulfonylureas and high-dose insulin regimens due to hypoglycemia risk.
3. Chronic Pain and Arthritis
- Preferred Medicines:
- Paracetamol (first-line for osteoarthritis).
- Topical NSAIDs (reduce systemic exposure).
- Avoid: Long-term oral NSAIDs and opioids unless necessary due to GI, renal, and dependency risks.
4. Insomnia and Anxiety
- Preferred Medicines:
- Non-drug therapies like cognitive-behavioral therapy (CBT) are first-line.
- Short-term use of low-dose melatonin or trazodone may be considered.
- Avoid: Long-acting benzodiazepines (e.g., diazepam) and Z-drugs (e.g., zolpidem) due to fall risk and cognitive impairment.
5. Depression
- Preferred Medicines:
- SSRIs (e.g., sertraline, citalopram).
- Avoid: Tricyclic antidepressants (e.g., amitriptyline) due to anticholinergic effects and risk of orthostatic hypotension.
6. Cognitive Impairment (Dementia)
- Preferred Medicines:
- Acetylcholinesterase inhibitors (e.g., donepezil).
- Memantine for moderate to severe cases.
- Avoid: Anticholinergics and benzodiazepines, which worsen cognitive function.
7. Constipation
- Preferred Medicines:
- Bulk-forming laxatives (e.g., psyllium).
- Osmotic laxatives (e.g., polyethylene glycol).
- Avoid: Stimulant laxatives for long-term use unless necessary.
8. Heart Failure
- Preferred Medicines:
- ACE inhibitors/ARBs.
- Beta-blockers (e.g., carvedilol).
- Mineralocorticoid receptor antagonists (e.g., spironolactone).
- Avoid: NSAIDs and certain calcium channel blockers (e.g., verapamil).
Commonly Used Medications to Avoid in the Elderly (Beers Criteria)
- Benzodiazepines: Increased sedation and fall risk.
- First-Generation Antihistamines: Anticholinergic effects, cognitive impairment.
- NSAIDs: GI bleeding, renal toxicity.
- Anticholinergics: Confusion, constipation, urinary retention.
Side Effects of Medicines in the Elderly
Common Side Effects
- Drowsiness or confusion.
- Dizziness and increased fall risk.
- Constipation or urinary retention.
Rare but Serious Side Effects
- Delirium from opioids or anticholinergics.
- Renal failure from NSAIDs.
- Hypoglycemia from sulfonylureas.
Monitoring and Follow-Up
- Regular renal and liver function tests for drugs with hepatic or renal metabolism.
- Monitor blood pressure and electrolyte levels for antihypertensives and diuretics.
- Assess for signs of toxicity or side effects during routine visits.
Patient Counseling Points
- Take medications exactly as prescribed; avoid skipping doses or doubling up.
- Use a pill organizer or medication tracker to ensure adherence.
- Avoid self-medicating with over-the-counter drugs or supplements without consulting a doctor.
- Report unusual symptoms like confusion, dizziness, or unusual bleeding promptly.
- Maintain a list of all medications, including supplements, to share with healthcare providers.
FAQs About Medicine Use in the Elderly
Q1: Why are elderly patients more sensitive to medications?
- Aging affects drug metabolism, distribution, and excretion, making older adults more prone to side effects and toxicity.
Q2: What is polypharmacy, and why is it a concern?
- Polypharmacy refers to using multiple medications, increasing the risk of interactions, side effects, and non-adherence.
Q3: How often should medications be reviewed?
- At least once a year or whenever there is a new health condition or medication change.
Q4: Can elderly patients take NSAIDs for arthritis?
- NSAIDs should be avoided or used sparingly due to risks of GI bleeding and kidney damage; paracetamol is safer.
Q5: What should elderly patients do if they miss a dose?
- Take it as soon as remembered unless it’s close to the next dose; never double up doses.
Q6: How can I reduce the risk of falls while on medications?
- Avoid sedatives, ensure proper lighting, and use assistive devices if necessary.
Q7: Can herbal supplements interact with prescribed medications?
- Yes, supplements like ginkgo biloba and St. John’s Wort can interfere with blood thinners and antidepressants.
Q8: Are antidepressants safe for elderly patients?
- SSRIs like sertraline are safer than older drugs like tricyclic antidepressants.
Q9: What medications should be avoided in elderly patients with dementia?
- Avoid anticholinergics and benzodiazepines, as they worsen cognitive impairment.
Q10: How can elderly patients manage medication schedules?
- Use a pill organizer, set reminders, or seek help from caregivers.
Q11: Are there safer alternatives to sleeping pills for the elderly?
- Yes, non-drug therapies like good sleep hygiene and melatonin are safer options.
Q12: Why are diuretics risky for elderly patients?
- They can cause dehydration, electrolyte imbalances, and increased fall risk.
Q13: What are the signs of medication toxicity in the elderly?
- Symptoms like confusion, severe drowsiness, or unusual bleeding may indicate toxicity.
Q14: Can elderly patients use over-the-counter pain relievers?
- Paracetamol is safer than NSAIDs; consult a doctor before use.
Q15: How can caregivers help manage medications for elderly patients?
- Monitor for side effects, help organize medications, and accompany them to doctor visits for medication reviews.