Drug Interactions between aspirin / calcium carbonate and tofacitinib

MONITOR: Chronic administration of antacids may reduce serum salicylate concentrations in patients receiving large doses of aspirin or other salicylates. The mechanism involves reduction in salicylate renal tubular reabsorption due to urinary alkalinization by antacids, resulting in increased renal salicylate clearance. In three children treated with large doses of aspirin for rheumatic fever, serum salicylate levels declined 30% to 70% during coadministration with a magnesium and aluminum hydroxide antacid. Other studies have found similar, albeit less dramatic results. Antacids reportedly have no effect on the oral bioavailability of aspirin in healthy adults. However, administration of antacids containing either aluminum and magnesium hydroxide or calcium carbonate two hours before aspirin dosing led to reduced absorption of aspirin in uremic patients.

MANAGEMENT: Patients treated chronically with antacids (or oral medications that contain antacids such as didanosine buffered tablets or pediatric oral solution) and large doses of salicylates (i.e. 3 g/day or more) should be monitored for potentially diminished or inadequate analgesic and anti-inflammatory effects, and the salicylate dosage adjusted if necessary.

MONITOR: Coadministration of Janus kinase (JAK) inhibitors with corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), and/or opioids may increase the risk of gastrointestinal (GI) perforation. Patients with a prior history of peptic ulceration or diverticular disease may also have an increased risk. Adverse events of diverticulitis and GI perforation have been infrequently reported in clinical studies and postmarketing use of JAK inhibitors such as baricitinib, ruxolitinib, tofacitinib, and upadacitinib. However, the role of JAK inhibition in these events has not been determined. In studies with rheumatoid arthritis and ulcerative colitis patients, many were receiving background therapy with NSAIDs or corticosteroids.

MANAGEMENT: Caution is recommended when using JAK inhibitors in patients with a history of peptic ulceration or diverticular disease and in patients receiving concomitant treatment with drugs associated with an increased risk of GI perforation such as corticosteroids, NSAIDs, and opioids. Patients should be advised to contact their healthcare provider if they experience signs and symptoms of GI perforation such as severe abdominal pain, fever, chills, nausea, or vomiting.