Drug prescribing

The following are important points to keep in mind in the context of drug prescribing for older adults.

1. Adverse drug reactions are commoner in those who are prescribed more than 5 drugs to take per day. 
2. Any new symptom should be considered as a possible drug-related event first.
3. It is always safer to prescribe lower doses of drugs. Older adults can have reduced renal drug clearance even when renal function is apparently normal. 
4. Sedatives, antipsychotics, first-generation antihistamines and drugs with anticholinergic activity can increase the potential for adverse events including falls.  
5. Always check liver and renal function before prescribing drugs.
6. Be aware of interactions between prescribed medicines and herbal OTC products (example: ginko biloba with warfarin increases risk of bleeding)
7. Prescribing cascades are more common in older adults. This is the situation when an adverse drug event is misinterpreted as a new medical condition and additional drugs are prescribed. 
8. Visual and cognitive impairment can lead to errors in compliance to medication
9. Periodic review of medications must be done to remove whatever is not needed and to see that appropriate medicines are prescribed in the correct dose. 
10. The Beers criteria lists down inappropriate medication for older adults. 
11. Certain drug-drug interactions are more common with elderly. For example: co-trimoxazole with ACEI/ARB leading to hyperkalemia; warfarin with NSAIDS causing bleeding; warfarin with omeprazole leading to bleeding; long acting sulphonylurea with co-trimoxazole leading to hypoglycemia
12. H2 receptor antagonists should be avoided in patients with delirium. Aspirin for primary CV prevention is not recommended for older adults over age 70 years. 
13.