There are an estimated 34.1 million adults with diabetes, accounting for 13% of all US adults and a staggering 26.8% of US adults aged 65 or older.¹ Every day, patients with diabetes are in the aisles of local pharmacies in search of OTC products to help them with various symptoms, whether diabetes-related or not. What should pharmacists consider when helping these patients choose appropriate OTC products?

Topical Products for Tingling Pain

Patients with diabetes frequently come to the pharmacy in search of relief for peripheral neuropathy—but experts say pharmacists shouldn’t rush to recommend OTCs.

“[If I were] a community pharmacist, if somebody told me that they’re having pin and needles or tingling in their fingers or their toes, I’d actually recommend that they go back to their doctor because usually, that’s a sign that their diabetes is not under control,” said Candis M. Morello, PharmD, CDCES, FCSHP, FASHP, professor of clinical pharmacy at UC San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences in La Jolla, California. Morello is director of the diabetes intense medical management clinic at the Veterans Affairs San Diego Healthcare System, where her team creates unique treatment protocols for very complex patients with type 2 diabetes.

According to Morello, when glycemic control is improved, diabetes complications, including peripheral neuropathy, are “absolutely reversible.” She found that this usually takes about 3 months using a multiprong approach, including diet, exercise, and drug therapy. In the interim, there is a place for OTC treatment for peripheral neuropathy.

Although the supplement α-lipoic acid has demonstrated positive effects on peripheral neuropathy, Morello is hesitant to recommend it to patients who are already taking a slew of oral prescription drugs. She prefers topical options, including capsaicin cream (0.075% 4 times daily, according to the American Academy of Neurology²) and lidocaine patches.

Morello said patients should be cautioned to wash hands well—including under their nails—after using capsaicin cream to avoid accidentally getting it in their eyes. Lidocaine patches can be cut to fit the affected area and may be worn for up to 12 hours per day.³

In considering the root cause of peripheral neuropathy, pharmacists should determine whether the patient is a smoker, as smoking can decrease blood flow to extremities and lead to nerve pain, noted Danielle Hambrick, PharmD, manager of a Walgreens pharmacy in downtown Chicago, Illinois. According to her, this symptom might be the impetus for patients with diabetes to quit smoking. Pharmacists can assist such patients in selecting smoking cessation aids, such as nicotine patches for long-term control and nicotine gum for breakthrough cravings.

Foot Care Pharmaceuticals

“Ulcers, amputations, all of that is preventable,” Morello said, as long as patients look at their feet every single day and visit their physician at the first sign of a problem. Hambrick added that any sign of infection on the feet, such as an open wound, swelling, or fever, is a huge red flag and should be referred to the patient’s physician. 

OTC moisturizers are important in the prevention of foot problems. “If you have dry skin, you can get fissures, and bacteria and fungi love to invade and cause infection,” Morello explained. There are a variety of diabetic foot creams on the market; she recommends those containing urea or ammonium lactate. Hambrick pointed out that moisturizers should only be used on the tops and soles of feet, not between the toes, which could lead to fungal growth.

According to Hambrick, patients with diabetes should be educated about proper foot care. This includes always drying feet entirely after bathing and protecting feet by wearing socks in the house and shoes outside. Nail files are preferred for cutting toenails, but if clippers must be used, they should only be straight-edged, not curved, to avoid cutting the skin.

Vitamins and Supplements

Although various vitamins and supplements are promoted for diabetes, there is limited data on their efficacy. In fact, supplements such as St. John’s wort, prickly pear cactus, aloe, and ginseng may interact with conventional diabetes drugs. Certainly, patients should not take dietary supplements in place of medications they have been prescribed for diabetes.⁴

Studies have found that various vitamins play a role in glucose metabolism and the risk for diabetes and its complications, but there is not enough data to recommend routine supplementation in the general population with diabetes. An exception is vitamin B12 supplementation in patients with type 2 diabetes taking metformin. Patients should be encouraged to eat a varied diet to ensure sufficient vitamin intake.⁵

Although the American Diabetes Association does not recommend routine multivitamins for patients with diabetes, Morello said that she and the dieticians she works with still recommend multivitamins because it can be difficult for patients to get all their nutrients solely from food sources.

Morello noted that patients who decide to take dietary supplements should be urged to choose only products that have been validated by a third party, such as the USP Dietary Supplement Verification Program or ConsumerLabs.com. “You just want to make sure that it was manufactured properly, that the amount and concentration that it says is in the bottle is actually in the bottle,” she said. “They’re spending valuable money, and we want to make sure they’re getting a product that actually contains what it says it does.”

Other Illnesses

Pharmacists should be mindful that patients seeking relief from cold and flu symptoms might also have diabetes. “Any patient that comes up with an over-the-counter question, there's always a chance they could [have] diabetes, so part of our counseling is making sure that we understand their pre-existing conditions,” said Hambrick. These patients should be counseled to steer clear of products containing sugar, including cold syrups and throat lozenges. Fortunately, there are still many options labeled sugar-free. They should also avoid products containing pseudoephedrine and other nasal decongestants, as they have been shown to increase blood glucose.

Hambrick noted that pharmacists should make sure patients with diabetes who have respiratory infections have an adequate supply of test strips. “Any time that a diabetic patient is ill, even if they're well controlled outside of that illness… they may have fluctuations with their blood glucose control, so they may need to test a little bit more often,” she said. These patients should also stock up on glucose tablets, she added, in case their blood sugar drops as a result of reduced appetite during illness.

According to Morello, for patients with diabetes complaining of constipation, psyllium is in excellent choice because it increases fiber intake and has been shown to decrease postprandial glucose concentrations.

Hambrick also stressed the importance of making sure patients with diabetes are adequately vaccinated. “With diabetes, your immune system is a little bit more compromised, and so those things like flu and pneumonia can be more severe,” she explained.

References

1. National diabetes statistics report, 2020. Centers for Disease Control and Prevention. Accessed December 7, 2020. https://www.diabetesresearch.org/file/national-diabetes-statistics-report-2020.pdf.
2. AAN summary of evidence-based guideline for clinicians: Treatment of painful diabetic neuropathy. American Academy of Neurology. 2011. Accessed December 7, 2020.
3. Lidocaine transdermal patch. Medline Plus. Last updated March 15, 2016. Accessed December 7, 2020. https://medlineplus.gov/druginfo/meds/a603026.html
4. Diabetes and dietary supplements. National Center for Complementary and Integrative Health. Last updated May 2018. Accessed December 7, 2020. https://www.nccih.nih.gov/health/diabetes-and-dietary-supplements#:~:text=For%20example%2C%20chromium%20might%20help,diabetic%20neuropathy%20(nerve%20problems)
5. Valdés-Ramos R, Guadarrama-López AL, Martínez-Carrillo BE, Benítez-Arciniega AD. Vitamins and type 2 diabetes mellitus. Endocr Metab Immune Disord Drug Targets. 2015;15(1):54-63. doi:10.2174/1871530314666141111103217