Drug Interactions between budesonide and dexamethasone / moxifloxacin

MONITOR CLOSELY: Concomitant administration of corticosteroids may potentiate the risk of tendinitis and tendon rupture associated with fluoroquinolone treatment. The mechanism is unknown. Tendinitis and tendon rupture have most frequently involved the Achilles tendon, although cases involving the rotator cuff (the shoulder), the hand, the biceps, and the thumb have also been reported. Some have required surgical repair or resulted in prolonged disability. Tendon rupture can occur during or up to several months after completion of fluoroquinolone therapy.

MANAGEMENT: Caution is recommended if fluoroquinolones are prescribed in combination with corticosteroids, particularly in patients with other concomitant risk factors (e.g., age over 60 years; recipient of kidney, heart, and/or lung transplant). Patients should be advised to stop taking the fluoroquinolone, avoid exercise and use of the affected area, and promptly contact their physician if they experience pain, swelling, or inflammation of a tendon. In general, fluoroquinolones should only be used to treat conditions that are proven or strongly suspected to be caused by bacteria and only if the benefits outweigh the risks.

MONITOR: Concomitant use of orally and rectally administered formulations of budesonide with inducers of CYP450 3A4 may decrease budesonide systemic as well as local exposure at the gut mucosa. Budesonide undergoes extensive first-pass and systemic metabolism via intestinal and hepatic CYP450 3A4. Although clinical and pharmacokinetic data are currently lacking, such an interaction may impact the therapeutic efficacy of budesonide in the treatment of inflammatory bowel disease.

MANAGEMENT: The potential for diminished pharmacologic effects of orally and rectally administered budesonide should be considered during concomitant treatment with drugs that induce CYP450 3A4. Alternative treatments or budesonide dose adjustments may be required if an interaction is suspected.