Monu Khanna, MD: Practical Pain Management Tips for Patients with Obesity

Managing pain in patients with obesity can be particularly challenging for clinicians, requiring more than just addressing the pain itself. It also involves understanding the broader metabolic and physiological factors that these patients often deal with. In a recent interview with Patient Care, Monu Khanna, MD, a board-certified obesity medicine and internal medicine expert, discussed how to approach pain management in this patient group.

Patients with obesity often have additional health concerns, like diabetes, cardiovascular disease, and airway issues, which can complicate pain treatment. Dr Khanna emphasized the need for caution when adjusting medication dosages. While increasing doses may seem like a straightforward solution, it can come with a higher risk of complications, including respiratory problems and liver damage. Patients with obesity may also metabolize drugs differently, which means that the typical dosing guidelines might not always apply.

Take acetaminophen, for example. It is commonly used for pain relief, and the usual guideline is to limit the dose to no more than 3 or 4 grams per day. But in patients with obesity, this amount might not be effective for pain management. This can lead clinicians to inadvertently increase the dose, which raises the risk of liver toxicity and gastrointestinal side effects. Research into how acetaminophen behaves in patients with obesity has shown that the drug’s metabolism can be altered, leading to concerns about appropriate dosing.¹

Pain management for these patients requires careful consideration of both medication options and non-drug treatments. Physicians should keep a close eye on potential side effects, be mindful of medication overuse, and account for the individual health factors that each patient brings to the table.

For primary care physicians, understanding the complexities of managing pain in patients with obesity is crucial. With the rise in obesity rates, these challenges are only going to become more common.²

In the video above, Dr Khanna offers practical advice on how to navigate pain management in patients with obesity, emphasizing individualized treatment plans and safe medication practices.

The following transcript has been edited for clarity, flow, and style.

Patient Care: What advice would you give to clinicians when developing pain management plans for patients with obesity?

Monu Khanna, MD: It’s very tricky because you don’t want to under-treat the pain, but at the same time, you have to be careful. Patients with obesity often have other metabolic issues, such as diabetes or heart disease. As you increase their medication doses, you have to consider that individuals with obesity might also have underlying airway issues. This makes them more prone to complications, such as respiratory compromise, due to the accumulation of high doses of medication. Additionally, we’re not always aware of how drugs metabolize in people who have excess fat stores.

On top of that, we lack accurate guidelines for dosing medications in these patients. We're constantly faced with a higher chance of complications. Take acetaminophen, for example. The usual guideline recommends no more than three or four grams a day as a safe dosage. However, in patients with obesity, it can be difficult to manage this. At that level, acetaminophen may not provide adequate pain relief, so clinicians may be tempted to increase the dose. But this can lead to liver damage, gastrointestinal side effects, or other issues.

Sources:

1. O'Brien, KD, et al. "Pharmacokinetics and Pharmacodynamics of Acetaminophen in Obesity: Implications for Pain Management." Clinical Pharmacology & Therapeutics, 2019.
2. Wadden, T.A., et al. "Obesity and Pain: A Comprehensive Review." Obesity Reviews, 2020.