Nitrofurantoin relies on kidney clearance to achieve high concentrations in the urine, which are necessary to treat lower urinary tract infections effectively. When creatinine clearance falls below a certain point, these urinary levels become unreliable and the drug may accumulate, raising the risk of toxicity without providing real benefit. The Beers Criteria specify avoiding nitrofurantoin when CrCl is below 30 mL/min because at or under this threshold the drug is neither effective nor safe for most older adults. The other values listed are not the cutoff used in this guideline. CrCl values like 60, 40, or 50 mL/min are higher than the threshold and do not mandate avoidance according to the Beers Criteria, whereas the critical caution is specifically at less than 30 mL/min.

Beers Criteria flags that prasugrel and ticagrelor carry a higher risk of major bleeding in older adults compared with clopidogrel, and this risk is especially pronounced in those aged 75 and older. Because of that heightened bleeding risk, if prasugrel is considered for someone in this age group, a lower dose of 5 mg is recommended to help mitigate harm. Ticagrelor also requires careful consideration in older patients due to bleeding risk, rather than routine use without adjustment. The other statements imply no difference in bleeding risk, routine use without dose changes, or a blanket contraindication for all older adults, which isn’t consistent with the guidance. The emphasis is on the increased bleeding risk in people 75 and older and the need for a reduced prasugrel dose SAMPLEif it’s used.

The key idea is that drugs which block dopamine in the nigrostriatal pathway tend to worsen Parkinson disease motor symptoms, so antipsychotics differ in how much they disrupt that pathway. Haloperidol is a potent D2 blocker with a high risk of extrapyramidal symptoms, making it more likely to aggravate PD. Quetiapine, on the other hand, has relatively weak and transient D2 receptor blockade and a broader receptor profile, so it produces far fewer extrapyramidal effects. This lower risk of worsening motor symptoms is why quetiapine is favored in Parkinson disease-related psychosis and is noted as an exception in Beers Criteria guidelines for older adults. Clozapine also has low EPS risk, but it carries a significant risk of agranulocytosis and requires regular blood monitoring, which limits its designation as a general exception. Olanzapine can be safer for EPS than haloperidol but has other drawbacks like metabolic effects, so those factors are why it’s not the standout exception here.

Beers Criteria guidance highlights that in older adults, the risk of falls and fractures rises with polypharmacy, especially when several central nervous system–active drugs are used together. Each CNS-active medication can cause sedation, dizziness, impaired coordination, cognitive slowing, or orthostatic hypotension. When three or more CNS-active medications are taken concurrently, these effects can compound, leading to a notably higher risk of falls and fractures than with fewer agents. CNS-active drugs include benzodiazepines and other sedative-hypnotics, antidepressants with sedating or anticholinergic properties, antipsychotics, anticonvulsants with CNS effects, and opioids. In practice, this means carefully reviewing a patient’s complete med list, avoiding unnecessary duplication of CNS-active drug classes, and considering deprescribing or substituting safer alternatives whenever possible. Emphasize nonpharmacologic approaches for sleep, mood, pain, and anxiety, and use the lowest effective dose for the shortest duration if a CNS-active medication is truly needed.