Case Studies: March 2022

Q. CS is a 44-year-old woman who calls with questions about zinc supplements. She recently listened to a podcast and heard that zinc may be helpful in managing COVID-19 infections, and she first tested positive for COVID-19 more than a week ago. Despite some symptomatic improvement, CS continues to test positive and wants to know if taking zinc will shorten the duration of illness.

What should the pharmacist recommend?

A. Zinc purportedly inhibits viral replication and attachment to the nasopharyngeal mucous. Evidence from in vitro studies suggests that zinc modifies the effects of several respiratory pathogens, including SARS-CoV-2. However, no reputable studies have evaluated zinc for COVID-19 management. Advise CS that consumption of zinc is not likely to improve her recovery time or symptoms. If she chooses to take zinc, advise her to avoid the nasal preparation because of reports of permanent loss of smell and taste. Oral zinc can cause adverse effects, including dose-related diarrhea, gastrointestinal upset, and metallic taste. Oral doses should not exceed the tolerable upper limit of 40 mg daily.

Reference

Adams KK, Baker WL, Sobieraj DM. Myth busters: dietary supplements and COVID-19. Ann Pharmacother. 2020;54(8):820-826. doi:10.1177/1060028020928052

Q. TN is a 37-year-old man with a body mass index (BMI) of 36 kg/m2, who recently went to his primary care physician (PCP) for a wellness visit. TN takes ergocalciferol 50,000 units once weekly. He generally feels well and has
no complaints today. His medical history is significant for morbid obesity, obstructive sleep apnea, tobacco abuse, and vitamin D deficiency. TN has had laboratory work done, and the results were unremarkable, apart from an glycated hemoglobin A1C level of 5.7% (eAG = 117 mg/ dL), a fasting glucose level of 108 mg/dL, and a TG level of 154 mg/dL. The PCP asks the pharmacist if TN should start taking metformin for the management of prediabetes.

A. TN should start on metformin if no other contraindications exist. Evidence from the Diabetes Prevention Program (DPP) shows that metformin can lower the chance of developing type 2 diabetes (T2D) by 31%. In the DPP trial, metformin was most effective for individuals aged between 25 and 44 years, patients with obesity with a BMI of 35 or higher, and women with a history of gestational diabetes. In addition to metformin therapy, the pharmacist should counsel TN on lifestyle modifications, including an individualized reduced-calorie meal plan and weight loss efforts. These lifestyle modifications can also delay the progression to T2D.

Reference

Knowler WC, Barrett-Connor E, Fowler SE, et al; Diabetes Prevention Program Research Group. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002;346(6):393- 403. doi:10.1056/NEJMoa012512

Stefanie C. Nigro, PharmD, BCACP, CDCES, is an associate clinical professor in the Department of Pharmacy Practice at the University of Connecticut School of Pharmacy in Storrs.