NR 508 Week 8 Polypharmacy Prescribing Cascade Paper Example

Ten Medicines Read as a History: An 81-Year-Old Widow Whose Amlodipine Led to Furosemide, Whose Furosemide Led to Potassium and a Bladder Pill Under Discussion, With Two Drugs Doing One Job and a Meclizine Nobody Can Place

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College of Nursing, Chamberlain University

NR 508: Advanced Pharmacology

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Month Day, Year

Ten Medicines Read as a History: An 81-Year-Old Widow Whose Amlodipine Led to Furosemide, Whose Furosemide Led to Potassium and a Bladder Pill Under Discussion, With Two Drugs Doing One Job and a Meclizine Nobody Can Place

The List as a History

Mrs. W., 81, lives alone since her husband died and was referred for a medication review after a fall at home. Her pharmacy record and her own account allow each medicine to be dated and tied to a reason.

In 2016 she started lisinopril 20 mg for hypertension. In 2019, because her blood pressure remained high, amlodipine 10 mg was added. About three months later she complained of swollen ankles and was started on furosemide 20 mg daily. Her potassium then fell, and potassium chloride 20 mEq was added in 2020. In 2021 a cardiologist started losartan 50 mg for blood pressure during a hospital stay, and it was continued at discharge. Omeprazole 20 mg was started during that admission for stomach protection. Atorvastatin 20 mg has been taken since 2015. Sertraline 50 mg was started in 2023 after her husband's death. Meclizine 25 mg at bedtime appears on every list since at least 2018, and no one, including Mrs. W., can say why. Last month she was given zolpidem 5 mg for sleep. Her primary care clinician is now considering oxybutynin because she is getting up three or four times a night to urinate. Her estimated glomerular filtration rate is 51 mL/min/1.73 m2.

Entries in Company: A Cascade

Read in order, the first four decisions are a chain. Amlodipine dilates arterioles more than veins and causes ankle edema that rises with dose; its prescribing information reports edema in more than one in ten patients taking the 10 mg dose, several times the rate at lower doses, and a higher rate in women (Viatris Specialty, 2025). The edema is not fluid overload, so a diuretic treats it poorly. Yet the furosemide started three months later was prescribed for exactly that. When the side effect of one medicine is mistaken for a fresh diagnosis and a second medicine is prescribed to treat it, the result is what geriatric pharmacology calls a prescribing cascade (Rochon & Gurwitz, 1997). It is common for this pair: in a population study of older adults with hypertension, people newly started on a calcium channel blocker were more likely to be dispensed a loop diuretic within months than people started on other antihypertensives, with the association strongest in the third month and seen when the analysis was restricted to amlodipine (Savage et al., 2020).

The cascade did not stop there. Furosemide caused potassium loss, which brought potassium chloride. It also increases urine output, and a loop diuretic taken daily is a plausible contributor to her nighttime urination. Oxybutynin, the drug now under discussion, would be the fourth link: a treatment for a symptom that may come from the second.

Two Doing One Job

Lisinopril and losartan both block the renin-angiotensin system, one by inhibiting angiotensin-converting enzyme and the other by blocking the angiotensin II receptor. Given together, they do the same job twice. For hypertension, combining them adds little blood pressure lowering and raises the risk of hyperkalemia, low blood pressure and kidney injury, particularly in an older woman with reduced kidney function. The losartan appears to have been started in hospital without the team noticing the lisinopril, and continued because no one reviewed the list as a whole. One of them should be stopped. Stopping losartan and keeping lisinopril, which she has taken for nine years, is the smaller change.

The pair also interacts with the cascade. The potassium supplement was added to offset furosemide, but two renin-angiotensin blockers both tend to raise potassium. Her potassium is now in the normal range, held there by drugs pushing in opposite directions, which becomes unstable the moment one of them is changed.

What an Addition Would Do

Oxybutynin is a strongly anticholinergic drug. The American Geriatrics Society Beers Criteria list strongly anticholinergic drugs as potentially inappropriate in older adults and warn in particular about combining multiple anticholinergic drugs, because of confusion, constipation, urinary retention and falls (American Geriatrics Society Beers Criteria Update Expert Panel, 2023). Mrs. W. already takes meclizine, an anticholinergic antihistamine, and zolpidem, which the same criteria list as a drug to avoid because of falls and fractures. She was referred after a fall. Adding oxybutynin would add a third centrally acting drug to a woman who has already fallen, to treat a symptom likely caused by her diuretic. The better first step is to address the diuretic.

The Entry Nobody Can Place

Meclizine has been taken nightly for at least seven years, and no one can say why. It may have been started for an episode of vertigo that has long since resolved. It is anticholinergic and sedating, and its effects add to those of zolpidem at bedtime, when she gets up repeatedly to use the bathroom. An entry with no current reason is the easiest to act on: the default for a medicine nobody can place is a supervised trial off it, with a plan to restart if dizziness returns.

The Remaining Entries

Atorvastatin has a clear, continuing reason in a woman her age with hypertension, and nothing in the review argues for stopping it. Sertraline has a reason tied to grief, and its continuation should be reviewed with her rather than assumed. Omeprazole was started for stomach protection during an admission and never reviewed; if she has no ongoing indication, it can be tapered and stopped.

The Order of Changes

The history suggests an order. First, stop the duplicated renin-angiotensin blocker, losartan, and recheck potassium and kidney function in one to two weeks. Second, lower amlodipine to 5 mg, or replace it with a different antihypertensive, to address the edema at its source; if the ankles improve, stop the furosemide, then the potassium chloride, with checks after each step. Third, stop meclizine. Fourth, reassess sleep and nighttime urination once the diuretic is gone, and try to stop zolpidem. Only if nighttime urination persists after all of that should a bladder medicine be considered, and then preferably one that is not strongly anticholinergic. Each step removes a link in the chain rather than adding one.

Mrs. W. should be part of the sequence, not its object. She should hear why each medicine is being changed, be given a written calendar of the changes and the blood tests, and be asked to report dizziness, swelling or a change in her sleep. A deprescribing plan fails most often when the patient is surprised by it and quietly resumes the old pills from the bathroom cabinet.

References

American Geriatrics Society Beers Criteria Update Expert Panel. (2023). American Geriatrics Society 2023 updated AGS Beers Criteria for potentially inappropriate medication use in older adults. Journal of the American Geriatrics Society, 71(7), 2052-2081. https://doi.org/10.1111/jgs.18372

Rochon, P. A., & Gurwitz, J. H. (1997). Optimising drug treatment for elderly people: The prescribing cascade. BMJ, 315(7115), 1096-1099. https://doi.org/10.1136/bmj.315.7115.1096

Savage, R. D., Visentin, J. D., Bronskill, S. E., Wang, X., Gruneir, A., Giannakeas, V., Guan, J., Lam, K., Luke, M. J., Read, S. H., Stall, N. M., Wu, W., Zhu, L., Rochon, P. A., & McCarthy, L. M. (2020). Evaluation of a common prescribing cascade of calcium channel blockers and diuretics in older adults with hypertension. JAMA Internal Medicine, 180(5), 643-651. https://doi.org/10.1001/jamainternmed.2019.7087

Viatris Specialty. (2025). Norvasc (amlodipine besylate) tablet [Prescribing information]. DailyMed, National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=7367289c-b0b0-466a-83e2-558e2985c29f