Derms on Drugs – "Obesity, GLP-1s and Dermatology"

Date: October 24, 2025
Hosts: Dr. Matt Zirwas, Dr. Laura Ferris, Dr. Tim Patton
Guest: Dr. Shanthi Narla (Medical College of Wisconsin)
Podcast: Scholars in Medicine

Episode Overview

This episode dives deep into the links between obesity, GLP-1 receptor agonists (GLP-1s), and inflammatory skin diseases – chiefly psoriasis and hidradenitis suppurativa (HS). The hosts—three dermatologists—blend educational insight with playful banter (and plenty of dad jokes) as they review recent studies, challenge the interpretive limits of big medical databases, and debate if dermatologists should be reaching for GLP-1s in daily practice. Special guest Dr. Shanthi Narla lends clinical and research expertise to elucidate mechanisms and address practical considerations.

Key Discussion Points & Insights

1. Obesity, Inflammation, and Skin Disease [00:02–02:56]

• Dr. Zirwas opens with a rapid-fire review of how obesity mediates systemic inflammation relevant to dermatology:
  • Adipokines (cytokines like leptin, adiponectin, resistin) from fat cells drive key inflammatory pathways (e.g., IL-6, TNF alpha, JAK-STAT).
  • Obesity promotes pro-inflammatory immune profiles—important for diseases like psoriasis and HS.
  • Adipose tissue can affect both skin and gut microbiomes.
• Key takeaway: There’s strong mechanistic plausibility for why obesity exacerbates skin inflammation.

2. GLP-1 Receptor Agonists in Psoriasis: Major Study Review [02:57–08:27]

• Dr. Ferris summarizes a cohort study (British Journal of Dermatology) analyzing GLP-1 users (e.g., semaglutide, liraglutide) versus other metabolic meds in psoriasis patients with obesity or type 2 diabetes:

  • Outcomes: all-cause mortality, major adverse cardiovascular events (MACE), psychiatric events, autoimmune sequelae.
  • Results:
    • 78% reduction in all-cause mortality
    • 44% reduction in MACE (including 65% lower stroke, 45% lower heart failure)
    • Reduced substance/alcohol abuse
  • Major limitation: No direct psoriasis severity scores (like PASI); can’t correlate improvement to skin specifically.

• Quote:

  "GLP1s actually had a pretty significant reduction in the comorbidities that we talk about a lot in our psoriasis patients." – Dr. Ferris [05:04]

• Banter:

  • Jokes about insurance claims for both “shots of insulin and shots of alcohol.” [06:20]

3. Is It Weight Loss or More? GLP-1s' Mechanisms and Direct Anti-inflammatory Effects [08:27–11:49]

• Panel debate: Does GLP-1’s benefit come only from weight loss or also from direct anti-inflammatory effects?

  • Dr. Narla: Evidence is mixed and mechanisms are unclear; possible action on various immune cells and adipokine modulation.
  • Need for more basic research, not just observational studies, to untangle causality.
  • Comorbidity reduction might arise from the “double whammy” of acting on both metabolic and immune axes in psoriasis.

• Quote:

  "I think GLP1, honestly in my brain, is kind of like dupilumab... it's just magical. It works on a lot of different things, and no one actually knows how." – Dr. Narla [10:24]

4. Limits of Observational Data: Confounders and Interpretation [11:49–13:46]

• Some comorbidities (e.g., fatty liver disease, sleep apnea, Crohn’s, psoriatic arthritis) were not reduced—”the devil’s in the details.”
• Dr. Ferris and Dr. Narla note the need for future data as dual-target drugs like tirzepatide enter the scene.

5. GLP-1 Physiology: How Do They Work? [13:46–16:49]

• Dr. Narla gives a primer:
  • GLP-1 (and GIP-1) are incretin hormones that respond to food intake, stimulating insulin release and suppressing glucagon.
  • Receptors are everywhere—brain, heart, stomach, kidney, vagus nerve—explaining wide-ranging effects, including early satiety and delayed gastric emptying.
  • Side effects can include delayed gastric emptying resulting in GERD (as experienced by Dr. Zirwas personally).
• Quote:

  "I was on some compounded tirzepatide... Well, it was great, I didn't eat anything, but I got this awful cough... It was asymptomatic GERD caused from delayed gastric emptying." – Dr. Zirwas [15:25]

6. GLP-1s in Hidradenitis Suppurativa (HS): Surgery Reduction? [17:23–25:43]

• Dr. Patton reviews a cohort study (Gupta et al.) suggesting HS patients on GLP-1s had fewer surgeries and hospitalizations:
  • Up to 75% fewer surgeries (95% with tirzepatide).
  • Found even in non-diabetic patients.
  • GLP-1s outperformed TNF inhibitors (adalimumab/infliximab) in this data.
• Skepticism abounds: All acknowledge limitations of the TriNetX database—possible flaws in coding, confounding, or even data misinterpretation.
  • Quote:

    "I talked to somebody who worked with Trinetics... they said, I don't even know if what we published is legit. Like, it's just so much data and you don't know." – Dr. Patton [19:54]

  • The effect size seems “too good to be true”; need for prospective, controlled studies.

7. GLP-1s in Atopic Dermatitis: Minimal Effect [26:16–28:43]

• Dr. Zirwas briefly reports a study in atopic dermatitis (AD):
  • Only 8% reduction in steroid use (possibly reflecting minimal clinical relevance).
  • AD isn’t as strongly linked to obesity as psoriasis or HS.

8. Should Dermatologists Prescribe GLP-1s? [28:43–39:01]

• Lively debate:

  • Many derms don't prescribe, but Dr. Narla does (and uses GLP-1s herself), believing in derms' competency to do so.
  • Important safety point: GLP-1s delay gastric emptying and may impair absorption of oral contraceptives—providers need to counsel on appropriate birth control.
  • Controversy over pharma programs offering GLP-1s cheaply with certain biologics (e.g., ixekizumab/Taltz), raising concerns about ethics and logistics.

• Quote:

  "I do think we have enough training to prescribe them… as far as I know, my own physicians… aren't really monitoring anything other than, you know, check in with me if you have any side effects." – Dr. Narla [28:43]

• Patient adherence: Most patients won’t stay on expensive drugs unless they see tangible benefit (weight loss, glycemic control).

9. Policy, Ethics, and Future Practice Considerations [31:30–39:01]

• Hosts discuss ethical/practical implications:
  • Should dermatologists steer patients toward biologics that unlock access to GLP-1s for $25/month?
  • Should they serve as a primary prescriber for obesity/diabetes medications?
  • Consensus: While dermatologists should address comorbidities and refer to PCPs, most would not manage primary obesity/diabetes care themselves—unless GLP-1s are someday directly FDA-approved for dermatologic diseases.
  • Quote:

    "I have opposed the whole comorbidity thing with derms getting as much into it as what some of the experts on comorbidities want us to… that's not our thing." – Dr. Patton [36:42]

Notable Quotes & Memorable Banter

• Best Dad Joke:

  "He was outstanding in his field." – Dr. Zirwas, on the best farmer in Ohio [06:35]

• On GLP-1s' Mystique:

  "I think GLP1, honestly in my brain, is kind of like dupilumab… it's just magical. It works on a lot of different things." – Dr. Narla [10:24]

• On Compounded Meds and Data Quality:

  "They're only looking at pharmacy prescriptions… they're not going to capture people who are on compounded medication." – Dr. Ferris [24:33]

• On patient priorities:

  "It's hard to get patients to stay on a medication for an unknown thing." – Dr. Ferris [23:43]

• On medical trivia:

  • Banter over "Fat Albert," King Henry VIII, and President Taft’s bathtub—used to lighten tone and connect to theme of obesity. [40:53–44:33]

Key Segment Timestamps

• Obesity & Inflammatory Pathways: 00:02–02:56
• BJD GLP-1s in Psoriasis Study: 02:57–08:27
• GLP-1 Mechanisms & Debate: 08:27–11:49
• Limitations and Drug Targets: 11:49–13:46
• GLP-1 Physiology Explained: 13:46–16:49
• HS Surgeries Study (Gupta et al.): 17:23–25:43
• GLP-1s in Atopic Dermatitis: 26:16–28:43
• Should Derms Prescribe GLP-1s?: 28:43–39:01
• Policy/Ethics of Drug Programs: 31:30–39:01
• End-of-Show Trivia: 40:53–44:33

Take-Home Points

• Obesity plays a clearly pro-inflammatory role in key dermatologic conditions.
• GLP-1s show major promise in reducing cardiovascular and psychiatric comorbidities in psoriasis patients—possibly through both weight loss and anti-inflammatory mechanisms, but causality remains unproven.
• Some big data findings (especially regarding HS surgery reduction) are striking but may be too good to trust without further validation.
• Dermatology’s role in GLP-1 prescribing is still evolving. Most agree comorbidity screening is essential, but primary management of diabetes and obesity should remain in collaboration with primary care.
• The panel agrees: More rigorous, clinically meaningful, and mechanistically-focused studies are needed before GLP-1s could become standard in dermatology practice.

Hosts’ Sign-off:
“I hope you learned a few things. I hope you laughed once or twice. But mostly, I’m hoping you’re planning to join us next week... And we are Derms on Drugs.”