Medical ConditionsEndocrine, GI & renal: Crohn disease

Crohn disease

Also called: Inflammatory bowel disease

Overview

Board takeaway: Review disease activity, nutrition, steroids, and immunosuppressants before invasive care; avoid nitrous oxide when methotrexate is used.

Oral lesions may precede bowel symptoms. Crohn disease causes patchy, transmural inflammation from mouth to anus; granulomas are supportive when present but are not required for diagnosis.

How does Crohn disease affect dental management?

Refer: persistent swelling or atypical ulcers warrant oral medicine/pathology assessment and possible biopsy.
Interpret biopsy: noncaseating granulomas support a differential that includes Crohn disease; they do not prove intestinal involvement.
Methotrexate: avoid nitrous oxide anesthesia because it can increase methotrexate toxicity; check planned antibiotics and analgesics for interactions. Prescribing information, Drug Interactions: Nitrous Oxide.
Before treatment: Review disease activity, nutrition, steroid exposure, and each immunosuppressant. Coordinate adrenal and infection precautions for the proposed procedure rather than assuming all patients need stress steroids or antibiotics
Flare prevention: Avoid NSAIDs; they can trigger flares
Oral treatment: Topical steroids for oral lesions; nutritional deficiency screening
After extraction: Acetaminophen is the first analgesic choice after extraction.

Scroll across to view all columns

Exposure or finding	Dental consequence
Methotrexate	Avoid nitrous oxide anesthesia and check planned drug interactions.
Steroid exposure	Assess adrenal suppression; obtain coverage when known or suspected, rather than automatically stress-dosing everyone.
Biologic/immunomodulator therapy	Review infections, monitoring, and cytopenias; coordinate relevant labs before surgery.
Active disease or poor nutrition	Reassess readiness, healing, and oral lesions with GI/oral medicine.

Exam pearl

What is Crohn disease?

A chronic immune-mediated inflammatory bowel disease that can affect any part of the digestive tract from mouth to anus, with patchy areas of inflammation separated by unaffected tissue.

What are the main systemic features of Crohn disease?

Onset and growth: Peak onset in adolescence; growth failure and delayed puberty in children
Symptoms: Abdominal pain, diarrhea, weight loss, perianal disease; anemia
Treatment: Treatment is individualized and may include nutritional therapy, short-term corticosteroids, immunomodulators (azathioprine or methotrexate), biologics, and surgery for complications

What oral findings occur in Crohn disease?

Cobblestoning of the buccal mucosa, mucosal tags, deep linear vestibular ulcers
Diffuse lip or facial swelling (granulomatous cheilitis), angular cheilitis
Aphthous ulcers, mucogingivitis
Pyostomatitis vegetans (more often with ulcerative colitis)

For Crohn disease, what do lip swelling, cobblestoning, and linear ulcers suggest?

Possible oral Crohn disease: this pattern can occur with orofacial granulomatosis, which may exist with or without intestinal Crohn disease. Oral lesions can precede gut symptoms
History: GI symptoms, weight loss, growth
Biopsy for noncaseating granulomas; pediatric gastroenterology referral

What should you assess before dental treatment in a patient with Crohn disease who takes infliximab and azathioprine?

Disease and immune status: ask about active infection, recent flares, medication monitoring, and prior cytopenias.
Before surgery: coordinate with gastroenterology whether a current CBC or other tests are needed; drug names alone do not define the risk.
Steroid exposure: establish dose, duration, discontinuation date, and any adrenal recovery testing; obtain an individualized dental/perioperative plan when suppression is a concern.
Drug-specific precautions: if the regimen includes methotrexate, avoid nitrous oxide because its interaction can increase methotrexate toxicity. This warning comes from prescribing information, not from the Crohn diagnosis.

Sources

Supplemental study guide: Pediatric Dental Study Guide: Crohn's Disease
Management Considerations for Pediatric Oral Pathology
Dental Management of Pediatric Patients Receiving Immunosuppressive Therapy and/or Head and Neck Radiation
Supplemental clinical source: NIDDK: Treatment for Crohn’s Disease
Supplemental clinical source: DailyMed: Methotrexate prescribing information — nitrous oxide interaction
AAPD best practice: AAPD: Antibiotic Prophylaxis for Dental Patients at Risk for Infection (2026)

Overview

Board takeaway: Review disease activity, nutrition, steroids, and immunosuppressants before invasive care; avoid nitrous oxide when methotrexate is used.

Oral lesions may precede bowel symptoms. Crohn disease causes patchy, transmural inflammation from mouth to anus; granulomas are supportive when present but are not required for diagnosis.

How does Crohn disease affect dental management?

Refer: persistent swelling or atypical ulcers warrant oral medicine/pathology assessment and possible biopsy.

Interpret biopsy: noncaseating granulomas support a differential that includes Crohn disease; they do not prove intestinal involvement.

Methotrexate: avoid nitrous oxide anesthesia because it can increase methotrexate toxicity; check planned antibiotics and analgesics for interactions. Prescribing information, Drug Interactions: Nitrous Oxide.

Before treatment: Review disease activity, nutrition, steroid exposure, and each immunosuppressant. Coordinate adrenal and infection precautions for the proposed procedure rather than assuming all patients need stress steroids or antibiotics

Flare prevention: Avoid NSAIDs; they can trigger flares

Oral treatment: Topical steroids for oral lesions; nutritional deficiency screening

After extraction: Acetaminophen is the first analgesic choice after extraction.

Scroll across to view all columns

Exposure or finding	Dental consequence
Methotrexate	Avoid nitrous oxide anesthesia and check planned drug interactions.
Steroid exposure	Assess adrenal suppression; obtain coverage when known or suspected, rather than automatically stress-dosing everyone.
Biologic/immunomodulator therapy	Review infections, monitoring, and cytopenias; coordinate relevant labs before surgery.
Active disease or poor nutrition	Reassess readiness, healing, and oral lesions with GI/oral medicine.

What are the main systemic features of Crohn disease?

Onset and growth: Peak onset in adolescence; growth failure and delayed puberty in children

Symptoms: Abdominal pain, diarrhea, weight loss, perianal disease; anemia

Treatment: Treatment is individualized and may include nutritional therapy, short-term corticosteroids, immunomodulators (azathioprine or methotrexate), biologics, and surgery for complications

What should you assess before dental treatment in a patient with Crohn disease who takes infliximab and azathioprine?

Disease and immune status: ask about active infection, recent flares, medication monitoring, and prior cytopenias.

Before surgery: coordinate with gastroenterology whether a current CBC or other tests are needed; drug names alone do not define the risk.

Steroid exposure: establish dose, duration, discontinuation date, and any adrenal recovery testing; obtain an individualized dental/perioperative plan when suppression is a concern.

Drug-specific precautions: if the regimen includes methotrexate, avoid nitrous oxide because its interaction can increase methotrexate toxicity. This warning comes from prescribing information, not from the Crohn diagnosis.