Derms on Drugs – Episode Summary

Episode Title: Why you shouldn't ever use Bactrim for acne (and other new info you don't want to miss)
Date: January 30, 2026
Hosts: Dr. Matt Zirwas, Dr. Laura Ferris, Dr. Tim Patton

Overview

This episode of Derms on Drugs features the panel's signature "six-pack" format, where Drs. Zirwas, Ferris, and Patton dive into six timely studies and hot topics from recent dermatology literature. The episode is packed with practical clinical pearls, lively debate, and sharp (occasionally self-deprecating) humor. The headline warning: vital new safety data makes Bactrim a dangerous—and potentially medico-legally risky—choice for acne management.

Key Discussion Points & Insights

1. Mediterranean Diet for Psoriasis (01:05–12:36)

• Study: JAMA Dermatology – Mediterranean diet in patients with psoriasis (Mediso RCT)
• Study Design: 16-week, open-label, evaluator-blinded RCT; 38 patients with mild-moderate psoriasis.
• Intervention: Full Mediterranean diet (dietitian support, monthly counseling, free olive oil).
• Findings:
  • Significant PASI reductions (3.4 mean decrease vs. 0 in controls).
  • 68% reached PASI 50, 47% PASI 75, 26% PASI 90 in Mediterranean group.
  • No significant weight loss or lipid changes, but improved DLQI and sleep.
  • Quote – Dr. Ferris:
    "They did not lose any weight, they just ate better and their psoriasis improved." (05:24)
• Practical Implication:
  • Mediterranean diet improves psoriasis independent of weight loss.
  • Diet likely works via microbiome modulation.
• Memorable Moment – On Olive Oil:
  "They also got.. free extra virgin olive oil. And they had to eat at least four tablespoons a day." (02:52)

2. Modifying Immunosuppression after cSCC in Transplant Patients (12:39–21:36)

• Study: Transplantation Direct – Consensus on immunosuppression after cutaneous SCC in kidney transplant patients.
• Key Points:
  • For 1 low-risk SCC, nephrologists seldom recommend immunosuppression (IS) changes.
  • For multiple/high-risk SCCs, consider switching mycophenolate or a calcineurin inhibitor to an mTOR inhibitor.
  • Panelists favor keeping CNI (e.g., tacrolimus) due to graft protection.
  • Dermatologists should match IS discussions to level of skin cancer risk.
• Clinical Debate:
  • Dr. Ferris suggests considering nicotinamide for lower-risk fields; both hosts note field therapy and oral preventives.
• Quote – Dr. Patton:
  "I think everyone kind of agrees...lots and lots of AKs...not the person where you need to call up the transplant team and say, hey, we should switch something." (16:46)

3. Atopic Dermatitis and Contact Sensitization Meta-Analysis (21:36–30:36)

• Study: Systematic review/meta-analysis on AD and risk of contact sensitization.
• Key Outcome:
  • No significant difference—patients with AD are neither more nor less likely than non-AD to have positive patch tests to contact allergens.
• Notable Findings:
  • AD patients slightly more likely to sensitize to sesquiterpene lactones (marigolds, chrysanthemums).
  • Diagnostic confusion may inflate apparent contact allergy rates in AD.
• Quote – Dr. Zirwas:
  "Main takeaway was we're now can be pretty sure that people with AD...they're no more or less likely to be allergic to anything compared to everybody else." (23:18)
• Humor:
  • "Get your AD friends chocolates, not flowers. That's the takeaway." (23:22, Dr. Ferris)

4. Dupilumab for Haley-Haley Disease – Promising Observational Data (30:36–27:26 [out of sequence])

• Study: Multicenter cohort; 20 patients; dupilumab in ATP2C1/“Haley-Haley” disease.
• Results:
  • 70% of cases: dramatic improvement, 20% improved, 10% no response.
  • Strong evidence for effectiveness; mechanism not entirely clear.
• Alternative Therapies Discussed:
  • Oral magnesium (300mg/day), apremilast, topical diclofenac, glycopyrrolate.
• Quote – Dr. Zirwas:
  "14 got, like, dramatically better. Like, so 70% got, like, shockingly better." (24:27)
• Naming Tangent:
  • Disease to be renamed ATP2C1-associated non-syndromic epidermal differentiation disorder.
  • "Yeah, because that rolls off the tongue." (27:44, Dr. Ferris)

5. Cosibelimab (PD-L1 Inhibitor) for Advanced cSCC (32:06–39:39)

• Study: Pivotal open-label—cosibelimab in metastatic/locally-advanced cSCC.
• Mechanism:
  • PD-L1 inhibitor with direct tumor lytic action.
• Results:
  • Objective response ~50%; complete response ~13-25%.
  • Durable responses; lower grade 3+ immune AEs than PD1 inhibitors.
• Quote – Dr. Ferris:
  "Kind of the take home, about half of people are going to respond and if they do, that's probably going to be a pretty durable response..." (35:10)
• Discussion Point:
  • PD-L1 status poorly correlated with response.
  • Highlights emerging role of this new, less toxic class.
• Memorable Moment:
  • "If I had a squam and they were talking to me about therapies, I would do the PD-L1. Like, it just makes way more sense." (37:58, Dr. Patton)

6. New Dermatomyositis Malignancy Prediction Tool (39:42–44:44)

• Study: JAMA Derm—TIP CA model for cancer risk in dermatomyositis.
• TIP CA Factors:
  • T: TIF1γ antibody
  • I: [no] Interstitial lung disease
  • P: Poikiloderma
  • C: Clinical diagnosis (DM vs. cutaneous only)
  • A: Anemia
• Implementation:
  • Points-based; cutoff at 2.5 separates lower vs. higher risk.
  • Similar to ICAMS model but with added poikiloderma, anemia.
  • Sensitivity (82%), specificity (66%).
• Quote – Dr. Patton:
  "If you have dermatomyositis and you don't want cancer, then you'd rather have interstitial lung disease." (42:21)
• Debate:
  • Original scoring inconsistencies; practical use vs. ICAMS tool.

7. Bactrim Warning – The Medico-Legal Bombshell (45:14–49:33)

• Key Point:
  • Recent FDA warning: Bactrim (TMP-SMX) in young, healthy patients for >7 days confers a 1 in 3,000 risk of fatal acute respiratory failure.
  • Most commonly prescribed for acne; the risk applies even in the absence of comorbidity.
• Discussion:
  • Risk much higher than SJS/TEN.
  • Need for extreme caution, particularly with long-duration Rx.
  • Co-hosts agree: Bactrim should be last-line; other options are safer.
• Quote – Dr. Zirwas:
  "If you're a derm and you prescribe Bactrim twice a week...over a 30 year career, that's going to be 3,000 people. You will kill one person from this reaction." (49:16)
• Reactions:
  • Dr. Ferris: "I hate Bactrim as a drug for acne and I'm always happy to have a reason not to give it." (47:45)
  • Dr. Patton: Comparison to other sulfas, but most data specific to Bactrim.

Notable Quotes & Segments by Timestamp

• [05:28] Dr. Ferris:
  "They did not lose any weight, they just ate better and their psoriasis improved."
• [23:22] Dr. Ferris:
  "Get your AD friends chocolates, not flowers. That's the takeaway."
• [24:27] Dr. Zirwas:
  "14 got, like, dramatically better. Like, so 70% got, like, shockingly better."
• [35:10] Dr. Ferris:
  "About half of people are going to respond and if they do, that's probably going to be a pretty durable response..."
• [37:58] Dr. Patton:
  "If I had a squam and they were talking to me about their therapies, I would do the PD-L1. Like, it just makes way more sense."
• [42:21] Dr. Patton:
  "If you have dermatomyositis and you don't want cancer, then you'd rather have interstitial lung disease."
• [49:16] Dr. Zirwas:
  "If you're a derm and you prescribe Bactrim twice a week...over a 30 year career, that's going to be 3,000 people. You will kill one person from this reaction."

Conclusion

• Key Takeaway:
  • Never use Bactrim for acne due to its unacceptable and under-recognized risk of fatal lung injury in young patients: "You will kill one person over your career if you use Bactrim liberally."
• Other Highlights:
  • Advise the Mediterranean diet for mild-to-moderate psoriasis.
  • Be familiar with evolving tools for immunosuppression management and malignancy risk in dermatomyositis.
  • Monitor new oncologic approvals, especially drugs with better safety profiles (cosibelimab).
  • Continue to scrutinize clinical literature with skepticism and humor.