Patient: Hermina Falck
Hermina Falck, an 85-year-old female has a past medical history of back and nerve pain, urinary incontinence, and gastroesophageal reflux disease (GERD). She also has limited mobility and requires a cane for stability. Upon enrollment in her healthcare program, she became eligible for her first annual health review. During her first review, Hermina had concerns about controlling her pain and improving urinary incontinence. Initially, her MedWise Risk Score™ was 27 (High).
A local, community-based pharmacist conducted multiple medication safety reviews (MSRs) from 2019 to 2021 to help improve Hermina’s quality of life. The MSRs focused particularly on pain management, deprescribing, and optimizing pharmacotherapy.
Initial Medication List:
- Alprazolam 1mg, 1 tablet by mouth daily
- Aspirin 81mg, 1 tablet by mouth daily
- Atorvastatin 10mg, 1 tablet by mouth daily
- Gabapentin 100mg, 1 capsule by mouth twice daily
- Calcium Citrate with Vitamin D3, 1 tablet by mouth twice daily
- Oxycodone 5mg; Acetaminophen 325mg, 1 tablet by mouth 3 times a day
- Ropinirole 2mg, 2 tablets by mouth daily
- Omeprazole 40mg delayed-release, 1 capsule by mouth once daily
- Methocarbamol 750mg, 1 tablet by mouth in the morning and 2 at bedtime
- Oxybutynin 5mg, 1 tablet by mouth twice daily
- Trimethoprim 100mg, 1 tablet by mouth daily
- Tylenol 500mg, 1–2 tablets by mouth twice daily
The pharmacist recognized several medication-related problems evidenced by Hermina’s high MedWise Risk Score. Of note, Hermina had a “very high” sedative burden, with the following contributing medications: alprazolam, gabapentin, methocarbamol, omeprazole, oxycodone, and ropinirole. Of these medications, alprazolam and methocarbamol are also included in the American Geriatrics Society Beers Criteria® as potentially inappropriate medications for older adults.
Problem 1: Inhibition of Oxycodone
The pharmacist identified several potential multi-drug interactions using the MedWise Matrix. Oxycodone is primarily metabolized to an active metabolite via the CYP2D6 enzyme. Fluoxetine, which has a higher affinity, is also metabolized by the CYP2D6 enzyme. When taken concomitantly, fluoxetine will competitively inhibit oxycodone. As a result, this interaction may lead to both reduced effectiveness (i.e., suboptimal pain control), and an increase in adverse effects (e.g., constipation, drowsiness, dizziness). Furthermore, omeprazole is a moderate affinity substrate of CYP3A4 and, when co-administered, may competitively inhibit the metabolism of oxycodone. This may further increase the risk of adverse effects.
Additionally, the pharmacist recognized Hermina’s pain regimen included subtherapeutic doses of gabapentin. Therapeutic dosing of gabapentin would reduce the need for oxycodone and mitigate the described CYP oxycodone interactions.
Problem 2: Unnecessary Medication
The clinical pharmacist also identified a potential unnecessary medication, omeprazole, which Hermina had been taking for over 10 years. Additionally, long-term use of proton-pump inhibitors (PPIs) can put participants at an increased risk for side effects, including bone loss and fractures, along with Clostridium difficile infection and gastritis. Lastly, fluoxetine causes a decrease in the activity of the CYP2C19. As a result, greater concentrations of the substrate omeprazole are expected to be observed further increasing the risk for adverse events.
Based on the reduction in Hermina’s risk score, she could see up to $16,592 in healthcare cost savings.1
Clinical Pharmacist Recommendations:
After reviewing Hermina’s medications and subjective information, the certified pharmacist provided the following recommendations for prescriber and patient consideration:
Consider changing oxybutynin to as needed or to mirabegron, which avoid the anticholinergic side effects and reduce sedative burden. In addition, non-pharmacologic alternatives are critical for improving urinary incontinence. These include performing Kegel exercises to strengthen the pelvic muscles, scheduling a voiding regimen with gradually increasing voiding intervals, and avoiding bladder irritants such as alcohol and caffeine.
Consider decreasing the dose of methocarbamol or changing methocarbamol to a medication that is not on the Beers list, such as baclofen, to reduce ADE risk.
Evaluate the continued need for PPI therapy (omeprazole 40mg capsule, delayed release) and consider discontinuing or reducing dose. Non-pharmacologic measures include refraining from alcohol, caffeine, spicy foods, and citrusy foods; avoiding large meals; and eating at least two to three hours prior to going to bed or lying down. Lastly, if continuing the PPI, regularly review magnesium and B12 levels.
Consider changing fluoxetine to a different medication, such as sertraline, to avoid the CYP interaction with oxycodone and omeprazole.
Consider increasing the dose of gabapentin to improve pain control. Also, consider deprescribing other pain medications such as oxycodone while maintaining a scheduled regimen of acetaminophen. If oxycodone is discontinued, the certified pharmacist will create a scheduled taper to avoid withdrawal reactions.
Consider discontinuing alprazolam and consider initiating or optimizing maintenance mood medications, as deemed appropriate. If a benzodiazepine is clinically indicated, consider a preferred alternative, such as lorazepam. Lorazepam does not undergo Phase I metabolism, which is often reduced in older adults.
Through four years of medication reviews, Hermina’s prescriber returned the following responses:
Accepted (changed to mirabegron)
Accepted (changed to baclofen)
Accepted (reduced dose to 20mg)
Accepted with changes (discontinued medication)
Accepted (increased dose of gabapentin and discontinued oxycodone with taper)
Accepted (changed to lorazepam)
Over the course of two years, Hermina was able to make significant medication changes to improve her MedWise Risk Score. Her risk score was reduced from 27 (high) to 11 (low).
The participant appreciated the individualized, high level of care she received from the pharmacist. Her pain has improved since her pain regimen was optimized, and she reports improvement in urinary symptoms. She also experienced significantly less daytime sedation.
Medication Risk Stratification and MedWise Risk Score
Risk stratification determines who is at the highest risk for ADEs and assigns a MedWise Risk Score between 0 and 50. The MedWise Risk Score is an indicator that helps pharmacists personalize patient regimens to improve safety and reduce preventable ADEs.