What is the recommended treatment approach for a patient with both ulcerative colitis (UC) and psoriasis?

Treatment Approach for Patients with Both Ulcerative Colitis and Psoriasis

For patients with both ulcerative colitis and psoriasis, TNF inhibitors (adalimumab, infliximab) or ustekinumab (IL-12/23 inhibitor) are the preferred systemic therapies, while IL-17 inhibitors must be strictly avoided due to risk of IBD exacerbation. 1

Medication Selection Algorithm

First-Line Biologic Options

TNF inhibitors are the optimal choice for treating both conditions simultaneously:

• Adalimumab is FDA-approved for both moderate-to-severe ulcerative colitis and moderate-to-severe plaque psoriasis, making it an ideal single-agent therapy 2
• Infliximab is similarly effective for both conditions and can be used when adalimumab is not suitable 1
• These agents address the shared inflammatory pathways in both diseases 1

Alternative Biologic Option

Ustekinumab (IL-12/23 inhibitor) is an excellent alternative:

• FDA-approved for both Crohn's disease and psoriasis 1
• Demonstrated effectiveness in phase 3 trials for IBD, including in TNF-blocker failures 1
• Can successfully treat both conditions when TNF inhibitors fail or cause paradoxical reactions 3
• Particularly valuable if the patient develops psoriasiform eruptions on TNF inhibitor therapy 3

Medications to Absolutely Avoid

IL-17 inhibitors (secukinumab, ixekizumab, brodalumab) are contraindicated in patients with IBD:

• Can cause paradoxical worsening of bowel disease 1
• In a randomized trial of 59 Crohn's disease patients, secukinumab showed reduced response, more adverse effects, and paradoxical IBD flares compared to placebo 1
• Case reports document de novo ulcerative colitis development during ixekizumab treatment for psoriasis 4
• The AAD-NPF guidelines explicitly recommend avoiding IL-17 inhibitors in IBD patients (Strength of Recommendation C, Level of Evidence I) 1

Dosing Regimens

For Adalimumab (treating both conditions):

Ulcerative Colitis induction: 2

• Day 1: 160 mg (single dose or split over two consecutive days)
• Day 15: 80 mg
• Day 29 and beyond: 40 mg every other week

Psoriasis dosing: 2

• Initial: 80 mg
• One week later: 40 mg every other week

Use the UC induction regimen initially, then maintain with 40 mg every other week for both conditions 2

For Ustekinumab (if TNF inhibitors fail):

• Follow Crohn's disease dosing protocols, which also benefit psoriasis 1
• Particularly useful in patients who develop paradoxical skin reactions to TNF inhibitors 3

Management of Paradoxical Reactions

If psoriasiform eruptions develop while on TNF inhibitor therapy for UC:

• First attempt: Add standard psoriasis treatments (topical corticosteroids, vitamin D analogues) while continuing the TNF inhibitor 1
• This approach achieves complete or partial skin clearance in 90% of cases (27/30 patients in systematic review) 1
• If skin disease persists despite adjunctive therapy: Switch to ustekinumab rather than discontinuing IBD treatment 1, 3
• Discontinuation of TNF inhibitor results in complete resolution in 94% (33/35 patients), but risks UC flare 1

Critical Monitoring Requirements

Screen for IBD symptoms in psoriasis patients before starting therapy: 1

• Chronic diarrhea, abdominal pain, rectal bleeding, unintentional weight loss
• The prevalence of ulcerative colitis is 1.64-1.91 times higher in psoriasis patients versus controls 1
• Crohn's disease prevalence is 2.49 times higher 1

Monitor for IBD exacerbation during psoriasis treatment: 1

• New or worsening gastrointestinal symptoms warrant immediate gastroenterology referral (Strength of Recommendation A) 1
• Particularly vigilant monitoring needed if considering IL-17 inhibitors (which should be avoided) 1

Special Considerations

Combination therapy considerations:

• TNF inhibitors combined with thiopurines or methotrexate show superior efficacy for UC remission compared to monotherapy 5
• This combination approach can benefit both the UC and psoriasis components 5

JAK inhibitors (tofacitinib, upadacitinib):

• FDA-approved for moderate-to-severe UC 5
• Reserve as second-line after TNF inhibitor failure 5
• Limited data for concurrent psoriasis treatment

Apremilast (PDE4 inhibitor):

• Case report demonstrates efficacy for psoriasis in a patient with concurrent primary sclerosing cholangitis and UC who failed adalimumab 6
• Consider as alternative in complex cases with multiple autoimmune conditions 6

Common Pitfalls to Avoid

1. Never prescribe IL-17 inhibitors to patients with known IBD or strong family history of IBD 1, 4
2. Do not prematurely discontinue TNF inhibitors if paradoxical psoriasiform eruptions develop—attempt adjunctive topical therapy first 1
3. Do not ignore gastrointestinal symptoms in psoriasis patients—the association is well-established and requires gastroenterology evaluation 1
4. Avoid switching between different 5-ASA formulations for UC if initial therapy fails—this is ineffective 5