Introduction to indocin and indomethacin
Indocin is a brand-name prescription medication containing the active ingredient indomethacin, a potent nonsteroidal anti-inflammatory drug (NSAID) belonging to the indoleacetic acid class. First approved by the United States Food and Drug Administration in 1965, indomethacin has been one of the most studied and widely used NSAIDs for the treatment of various inflammatory conditions. Indomethacin is recognized for its potent anti-inflammatory, analgesic, and antipyretic properties, making it effective for a range of conditions including moderate to severe rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, acute gouty arthritis, and other inflammatory disorders. The medication is available in several formulations including immediate-release capsules, extended-release capsules, oral suspension, and injectable solutions, providing flexibility in administration for different clinical scenarios.
Indomethacin is considered one of the more potent NSAIDs available, and it is often reserved for conditions that require robust anti-inflammatory therapy, such as acute gout flares and ankylosing spondylitis, or for patients who have not responded adequately to other NSAIDs. The potent therapeutic effects of indomethacin are accompanied by a correspondingly significant adverse effect profile, particularly regarding gastrointestinal toxicity, which has led to more cautious prescribing patterns in recent decades. The development of safer NSAIDs, including selective COX-2 inhibitors and other non-selective NSAIDs with more favorable safety profiles, has reduced the use of indomethacin as a first-line therapy for many conditions. However, indomethacin remains an important therapeutic option for specific indications where its potency provides unique benefits.
The mechanism of action of indomethacin involves potent inhibition of cyclooxygenase (COX) enzymes, specifically COX-1 and COX-2, which are responsible for the production of prostaglandins and other inflammatory mediators. Indomethacin is a non-selective NSAID that inhibits both COX isoforms with approximately equal potency, resulting in effective reduction of inflammation and pain and significant gastrointestinal and renal effects due to inhibition of COX-1-derived protective prostaglandins. The potency of indomethacin as a COX inhibitor is among the highest of the NSAID class, with in vitro studies showing that it inhibits COX activity at lower concentrations than most other NSAIDs. This high potency contributes to its therapeutic effectiveness and to its adverse effect profile.
The clinical use of indomethacin requires careful patient selection and monitoring due to its adverse effect profile and the availability of safer alternatives for many indications. Indomethacin is generally recommended for short-term use in acute conditions such as gout flares and for chronic use only when other NSAIDs have proven inadequate. The medication is available in various dosage forms and strengths, with immediate-release capsules typically containing 25 mg or 50 mg of indomethacin, extended-release capsules containing 75 mg, and oral suspension containing 25 mg per 5 mL. An injectable formulation is also available for hospital use, particularly for the management of patent ductus arteriosus in premature infants, which is a specialized indication unrelated to its use in adults for inflammatory conditions.
For patients who require indomethacin for their medical condition, access through various pharmacy channels including online platforms such as Happy Family Store can facilitate treatment. However, due to the potent nature of indomethacin and its significant adverse effect profile, it is essential that patients obtain this medication only from licensed and reputable sources and use it under the close supervision of a qualified healthcare provider who can assess the risks and benefits for their individual situation. Self-medication with indomethacin is not recommended, and patients should never exceed the prescribed dose or duration of therapy.
Medical uses and indications
The primary indication for indomethacin is the treatment of moderate to severe rheumatoid arthritis, including acute flares of the disease. Rheumatoid arthritis is a chronic systemic autoimmune disease characterized by symmetric polyarticular inflammation of the synovial joints, leading to pain, swelling, stiffness, and progressive joint destruction. Indomethacin is particularly effective in controlling the inflammatory manifestations of rheumatoid arthritis, including joint swelling, tenderness, and morning stiffness. The medication is typically used in patients with moderate to severe disease who have not responded adequately to other NSAIDs or who require more potent anti-inflammatory therapy. Indomethacin is usually administered as part of a comprehensive treatment plan that includes disease-modifying antirheumatic drugs (DMARDs) and other therapies for long-term disease management.
Ankylosing spondylitis is another condition for which indomethacin is highly effective. This chronic inflammatory disease primarily affects the axial skeleton, causing inflammation of the sacroiliac joints and spine, leading to chronic back pain, morning stiffness, and progressive spinal stiffness. Indomethacin has been considered one of the most effective NSAIDs for ankylosing spondylitis, with many patients experiencing dramatic improvement in symptoms, particularly nocturnal pain and morning stiffness that can interfere with sleep and daily activities. The potent anti-inflammatory effects of indomethacin help reduce spinal inflammation, improve mobility, and enhance quality of life in patients with this condition. The medication may be used alone or in combination with biologic therapies such as TNF inhibitors for more severe or refractory disease.
Acute gouty arthritis is a classic indication for indomethacin, and it has been considered one of the most effective treatments for acute gout flares for decades. Gout involves sudden, severe attacks of joint pain, redness, swelling, and tenderness resulting from the deposition of urate crystals in the joint. Indomethacin at appropriate doses provides rapid and effective relief from the intense pain and inflammation of acute gout, often within hours of administration. The typical dose for acute gout is 50 mg three times daily for the first few days, followed by rapid dose reduction as the flare resolves. Despite the development of newer treatments for acute gout, including colchicine and corticosteroids, indomethacin remains a valuable therapeutic option, particularly for patients with severe flares who require potent anti-inflammatory therapy.
Osteoarthritis, particularly when involving large weight-bearing joints such as the hips and knees, may be treated with indomethacin in patients who have not responded adequately to other NSAIDs. However, due to the availability of safer alternatives, indomethacin is generally not recommended as first-line therapy for osteoarthritis. When used for osteoarthritis, indomethacin should be administered at the lowest effective dose for the shortest possible duration, and patients should be monitored closely for adverse effects. The medication may be particularly useful for managing acute flares of osteoarthritis when inflammatory symptoms are prominent, but chronic use should be avoided when possible.
Acute shoulder pain conditions including bursitis and tendinitis respond well to indomethacin therapy. Subacromial bursitis, bicipital tendinitis, and rotator cuff tendinitis are common causes of shoulder pain that involve inflammation of the bursae or tendons around the shoulder joint. Indomethacin reduces local inflammation and pain in these conditions, helping to restore shoulder function and facilitate rehabilitation. Treatment for acute shoulder conditions is typically short-term, ranging from 7 to 14 days, and should be accompanied by appropriate physical therapy and activity modification to prevent recurrence. Indomethacin may also be used for acute musculoskeletal injuries involving other joints and soft tissues.
Patent ductus arteriosus (PDA) in premature infants is a unique and specialized indication for intravenous indomethacin. The ductus arteriosus is a fetal blood vessel connecting the pulmonary artery to the aorta that normally closes shortly after birth. In premature infants, the ductus may remain patent (open), leading to hemodynamic complications. Indomethacin promotes closure of the patent ductus arteriosus by inhibiting prostaglandin synthesis, as prostaglandins are essential for maintaining ductal patency in the fetus and newborn. This use of indomethacin in neonatal intensive care is quite distinct from its anti-inflammatory use in adults and involves specific dosing protocols and monitoring requirements that are managed by neonatologists.
Other inflammatory conditions for which indomethacin may be used include psoriatic arthritis, Reiter syndrome (reactive arthritis), and other seronegative spondyloarthropathies. Indomethacin has also been used for the management of dysmenorrhea, although other NSAIDs with more favorable safety profiles are generally preferred for this indication. The medication may be used off-label for pericarditis and other inflammatory conditions where potent NSAID therapy is required, although alternative treatments are often preferred. The use of indomethacin for these conditions should be guided by a specialist who can weigh the potential benefits against the risks of therapy.
Mechanism of action
The mechanism of action of indomethacin involves potent, non-selective inhibition of cyclooxygenase (COX) enzymes, specifically COX-1 and COX-2, which catalyze the conversion of arachidonic acid to prostaglandin H2, the precursor of prostaglandins, prostacyclin, and thromboxanes. Indomethacin is one of the most potent COX inhibitors among NSAIDs, with in vitro studies demonstrating inhibition of COX activity at nanomolar concentrations. This high potency means that indomethacin effectively reduces the production of pro-inflammatory prostaglandins at sites of inflammation, providing robust anti-inflammatory and analgesic effects. However, the non-selective nature of COX inhibition means that indomethacin also inhibits the production of protective prostaglandins in the gastrointestinal tract, kidneys, and other tissues, leading to its characteristic adverse effect profile.
The binding of indomethacin to COX enzymes involves rapid, reversible binding to both COX-1 and COX-2. Unlike some NSAIDs that exhibit time-dependent or slowly reversible binding, indomethacin binds to COX enzymes in a competitive and rapidly reversible manner. This binding kinetics profile means that the inhibitory effects of indomethacin on COX activity are directly related to its concentration at the enzyme active site, and that enzyme activity can recover relatively quickly as drug concentrations decline. The clinical consequence of this binding profile is that indomethacin must be dosed multiple times daily (typically two to four times daily depending on the formulation) to maintain consistent therapeutic effects, unlike the once-daily dosing possible with longer-acting NSAIDs like piroxicam.
Beyond COX inhibition, indomethacin has been shown to have additional mechanisms that may contribute to its pharmacological effects. Indomethacin can inhibit the activation and function of neutrophils, including chemotaxis, adhesion, and degranulation, which are important processes in the inflammatory response. The medication also affects the production of reactive oxygen species and the release of lysosomal enzymes from inflammatory cells. Indomethacin has been shown to modulate the activity of phospholipase A2, the enzyme that releases arachidonic acid from cell membrane phospholipids, thereby reducing the substrate availability for both COX and lipoxygenase pathways. These additional anti-inflammatory mechanisms may contribute to the overall therapeutic profile of indomethacin and help explain its effectiveness in conditions characterized by intense inflammation.
The pharmacokinetics of indomethacin vary depending on the formulation used. After oral administration of immediate-release capsules, indomethacin is rapidly and well absorbed from the gastrointestinal tract, with peak plasma concentrations achieved within one to two hours. Extended-release capsules provide slower absorption, with peak concentrations achieved in approximately four to six hours, followed by sustained release over 12 to 24 hours. The oral bioavailability of indomethacin is approximately 100 percent, and food does not affect the extent of absorption, although the rate may be slightly delayed. Indomethacin is bound to plasma proteins (approximately 90 percent) and has a volume of distribution of approximately 0.3 to 0.6 L/kg.
The metabolism of indomethacin occurs primarily in the liver through various pathways including O-demethylation, N-dechlorobenzoylation, and glucuronidation. The major metabolite, desmethylindomethacin, has some pharmacological activity, contributing to the overall effects of the medication. The elimination half-life of indomethacin is approximately 4.5 to 6 hours for the immediate-release formulation, supporting dosing three to four times daily for most indications. Extended-release formulations provide a longer apparent half-life that supports twice-daily dosing. Indomethacin and its metabolites are eliminated through both renal and biliary routes, with approximately 60 percent of the dose excreted in the urine and approximately 30 percent in the feces. The clearance of indomethacin may be reduced in elderly patients and those with renal or hepatic impairment, necessitating dose adjustment in these populations.
Dosage and administration
The dosage of indomethacin varies widely depending on the condition being treated, the severity of symptoms, the patient’s response to therapy, and individual tolerance. For moderate to severe rheumatoid arthritis and ankylosing spondylitis, the recommended starting dose of immediate-release indomethacin is 25 mg two to three times daily. The dose may be increased gradually to a maximum of 50 mg three to four times daily if adequate symptom control is not achieved at lower doses. For many patients, a total daily dose of 75 to 150 mg is sufficient for symptom control, while some patients with severe disease may require up to 200 mg daily. The extended-release formulation (75 mg capsules) is typically dosed once or twice daily, with a maximum of 75 mg twice daily for a total daily dose of 150 mg.
For acute gouty arthritis, the recommended dose of indomethacin is 50 mg three times daily. Treatment should be initiated as soon as possible after the onset of a gout flare for optimal effectiveness. The higher dose is typically continued for 3 to 5 days until the acute inflammation resolves, after which the dose should be rapidly reduced or the medication discontinued. The total duration of therapy for an acute gout flare rarely exceeds 7 to 10 days. Patients should be advised to keep indomethacin available at home so they can initiate treatment promptly at the first sign of a gout flare, as early treatment is associated with better outcomes.
For acute shoulder pain conditions such as bursitis and tendinitis, the recommended dose of indomethacin is 75 to 150 mg daily in divided doses for 7 to 14 days. The medication is typically started at the higher end of the dose range and gradually reduced as symptoms improve. For osteoarthritis and other chronic conditions, the lowest effective dose should be used, typically starting at 25 mg two to three times daily and adjusting based on response and tolerance. The total daily dose for osteoarthritis should not exceed 150 to 200 mg, and the need for continued therapy should be reassessed periodically.
Indomethacin capsules should be taken with food, milk, or an antacid to reduce the risk of gastrointestinal irritation. The capsules should be swallowed whole without crushing or chewing, particularly extended-release formulations, which should not be cut or crushed as this would alter the drug release characteristics. Patients should take indomethacin at evenly spaced intervals throughout the day to maintain consistent drug levels. If a dose is missed, it should be taken as soon as remembered, unless it is almost time for the next scheduled dose, in which case the missed dose should be skipped and the regular schedule resumed.
Special dosing considerations apply to elderly patients and patients with renal or hepatic impairment. Elderly patients are at increased risk of adverse effects from indomethacin, and the lowest effective dose should be used, typically starting at 25 mg twice daily. The dose should be increased slowly and only if needed, with careful monitoring for adverse effects. Patients with mild to moderate renal impairment may require dose reduction, and indomethacin is contraindicated in patients with severe renal impairment (creatinine clearance less than 30 mL/min). Patients with hepatic impairment should use indomethacin with caution, and the medication should be avoided in patients with active liver disease or elevated liver enzymes.
Adverse effects and safety profile
Gastrointestinal adverse effects are the most common and clinically significant side effects of indomethacin therapy, reflecting its potent non-selective COX inhibition. The most frequently reported gastrointestinal effects include dyspepsia (indigestion), epigastric pain, nausea, vomiting, diarrhea, constipation, and flatulence. More serious gastrointestinal events including gastric or duodenal ulcers, upper gastrointestinal bleeding, perforation, and obstruction are significant risks with indomethacin, with the risk being dose-dependent and increasing with duration of therapy. The incidence of gastrointestinal ulceration with indomethacin has been reported to be as high as 10 to 30 percent in some studies, which is among the highest rates for NSAIDs. Patients with risk factors including advanced age, history of peptic ulcer disease, concurrent use of corticosteroids or anticoagulants, and Helicobacter pylori infection are at highest risk.
Central nervous system adverse effects are particularly characteristic of indomethacin and are more common with this NSAID than with most others. Headache is the most frequent CNS effect, occurring in up to 25 percent of patients and sometimes requiring dose reduction or discontinuation. Dizziness, vertigo, somnolence (drowsiness), confusion, depression, and psychiatric disturbances including hallucinations and psychotic episodes have been reported, particularly in elderly patients. These CNS effects are thought to result from inhibition of prostaglandin synthesis in the central nervous system, where prostaglandins affect regulating various neurological functions. The high CNS penetration of indomethacin compared to other NSAIDs may contribute to these effects. Patients should be cautioned about the potential for CNS effects that could impair their ability to drive or operate heavy machinery.
Cardiovascular adverse effects associated with indomethacin include hypertension, fluid retention, peripheral edema, and increased risk of serious cardiovascular events including myocardial infarction and stroke. Indomethacin may also blunt the antihypertensive effects of various blood pressure medications, particularly beta-blockers, ACE inhibitors, and diuretics. The medication has been shown to increase blood pressure in both normotensive and hypertensive individuals, and this effect may be more pronounced with indomethacin compared to some other NSAIDs. Patients with preexisting hypertension should have their blood pressure monitored closely when starting indomethacin, and antihypertensive medications may need adjustment. Indomethacin should be used with caution in patients with established cardiovascular disease.
Renal adverse effects include fluid retention, edema, decreased urine output, and acute kidney injury, particularly in patients with preexisting renal impairment, heart failure, cirrhosis, or volume depletion. Indomethacin can cause significant reductions in renal blood flow and glomerular filtration rate through inhibition of prostaglandin-dependent renal vasodilation. Hyperkalemia may occur, particularly in patients with renal impairment or those taking potassium-sparing diuretics, ACE inhibitors, or angiotensin receptor blockers. The risk of renal adverse effects with indomethacin is higher than with many other NSAIDs due to its potent COX inhibition and the importance of prostaglandins in maintaining renal function in compromised kidneys.
Hematological adverse effects include inhibition of platelet aggregation, which can prolong bleeding time and increase the risk of bleeding complications. Indomethacin inhibits thromboxane A2 production through COX-1 inhibition in platelets, reducing platelet aggregation and hemostatic function. This effect is reversible and diminishes as the drug is cleared from the body. Patients taking anticoagulants such as warfarin are at increased risk of bleeding when indomethacin is added to their regimen, and prothrombin time should be monitored closely. Indomethacin may also cause bone marrow suppression, including aplastic anemia and agranulocytosis, although these effects are rare.
Other adverse effects include hypersensitivity reactions (urticaria, angioedema, anaphylaxis), dermatological reactions (skin rashes, photosensitivity, Stevens-Johnson syndrome), hepatotoxicity (elevated liver enzymes, hepatitis), and ototoxicity (tinnitus, hearing loss). Indomethacin may also cause corneal deposits and retinal disturbances with long-term use, although these effects are rare. The medication can cause increased serum potassium, increased blood urea nitrogen, and elevated liver enzymes, which should be monitored periodically during therapy.
Contraindications and precautions
Indomethacin is contraindicated in patients with known hypersensitivity to the drug or any component of its formulation, and in patients who have experienced allergic reactions to aspirin or other NSAIDs. Cross-sensitivity reactions among NSAIDs are common, and patients with a history of NSAID allergy should avoid indomethacin and all other NSAIDs. Indomethacin is also contraindicated in patients with active peptic ulcer disease or gastrointestinal bleeding, and in patients with a history of recurrent peptic ulcer disease or gastrointestinal bleeding, as the risk of exacerbation is substantial.
Cardiovascular contraindications include use of indomethacin for perioperative pain management in patients undergoing coronary artery bypass graft surgery. The medication should be avoided in patients with severe heart failure (New York Heart Association class III or IV) due to the risk of fluid retention and worsening cardiac function. Uncontrolled hypertension is a relative contraindication, and blood pressure should be adequately controlled before initiating indomethacin therapy. Patients with established cardiovascular disease should use indomethacin with extreme caution and only when alternative therapy is not available.
Renal contraindications include severe renal impairment (creatinine clearance less than 30 mL/min) and advanced renal disease. Indomethacin should be used with caution in patients with mild to moderate renal impairment, with appropriate dose reduction and monitoring of renal function. The medication should be avoided in patients with volume depletion. Hepatic contraindications include active liver disease or elevated liver enzymes. Indomethacin should be used with caution in patients with mild hepatic impairment.
Pregnancy and lactation considerations impose important restrictions on indomethacin use. Indomethacin is classified as pregnancy category C during the first and second trimesters and category D during the third trimester. The medication is contraindicated during the third trimester because NSAIDs can cause premature closure of the ductus arteriosus in the fetus, leading to pulmonary hypertension and other complications. Indomethacin may also impair fetal renal function, reduce amniotic fluid volume, and inhibit uterine contractions, potentially prolonging labor. The use of indomethacin in pregnancy, particularly after 32 weeks of gestation, is associated with significant fetal risks. Women who are trying to conceive should avoid indomethacin due to potential effects on ovulation and fertility.
Clinical studies and efficacy
The efficacy of indomethacin in rheumatoid arthritis has been established through numerous clinical trials spanning several decades. In comparative studies, indomethacin at doses of 100 to 200 mg daily was shown to be superior to placebo and at least as effective as other NSAIDs including aspirin, phenylbutazone, and ibuprofen in reducing joint pain, swelling, and morning stiffness. Indomethacin was particularly effective in controlling the inflammatory component of rheumatoid arthritis, with many patients experiencing rapid and substantial improvement in symptoms. However, the high rate of gastrointestinal and CNS adverse effects limited the tolerability and long-term use of indomethacin in many patients, contributing to its declining use as first-line therapy as safer NSAIDs became available.
In ankylosing spondylitis, indomethacin has demonstrated particular efficacy in controlling axial symptoms, including spinal pain and morning stiffness. Clinical studies have shown that indomethacin at doses of 75 to 150 mg daily provides superior symptom control compared to placebo and is at least as effective as other NSAIDs in managing ankylosing spondylitis. The medication has been shown to improve spinal mobility, reduce nocturnal pain that disrupts sleep, and enhance overall quality of life in patients with this condition. The potent anti-inflammatory effects of indomethacin are particularly valuable in ankylosing spondylitis, where inflammation of the axial skeleton can be severe and disabling.
The efficacy of indomethacin in acute gout has been shown in both controlled trials and extensive clinical experience. Indomethacin at doses of 50 mg three times daily provides rapid and effective relief from the intense pain and inflammation of acute gout flares, with most patients experiencing significant improvement within 24 to 48 hours. Comparative studies have shown that indomethacin is at least as effective as other NSAIDs, colchicine, and corticosteroids for acute gout, and it has been considered a standard therapy for this indication for many years. The rapid onset of action and potent anti-inflammatory effects of indomethacin make it particularly suitable for managing the severe inflammation associated with gout flares.
Frequently asked questions
Is Indocin available over the counter? No, Indocin (indomethacin) is a prescription-only medication in all countries due to its potent effects and significant adverse effect profile. Medical supervision is required to ensure appropriate use, dosing, and monitoring. Online pharmacies such as Happy Family Store may offer Indocin through various channels, but patients should always consult with a healthcare provider before using this medication.
How does indomethacin differ from other NSAIDs? Indomethacin is one of the most potent NSAIDs available, with greater anti-inflammatory potency than most other NSAIDs. This potency makes it particularly effective for conditions with intense inflammation, such as acute gout and ankylosing spondylitis. However, the potency also contributes to a higher rate of adverse effects, particularly gastrointestinal and central nervous system effects. Other NSAIDs with more favorable safety profiles are generally preferred as first-line therapy for most conditions.
Why is indomethacin used less frequently than other NSAIDs? Indomethacin use has declined over the years due to the availability of safer alternatives. The medication has a higher rate of gastrointestinal adverse effects, including ulcers and bleeding, compared to many other NSAIDs. It also has a characteristic profile of central nervous system effects, including headache and dizziness, that are more common with indomethacin than with most other NSAIDs. The development of selective COX-2 inhibitors and other safer NSAIDs has reduced the clinical need for indomethacin for most indications.
Can indomethacin be taken with other NSAIDs? No, indomethacin should not be taken with other NSAIDs, including over-the-counter products containing ibuprofen, naproxen, or aspirin. Combining NSAIDs increases the risk of gastrointestinal and renal adverse effects without providing additional therapeutic benefit. Patients who require additional pain relief should discuss appropriate options with their healthcare provider.
What are the most common side effects of indomethacin? The most common side effects of indomethacin are gastrointestinal, including dyspepsia, abdominal pain, nausea, vomiting, and diarrhea. Central nervous system effects, particularly headache, dizziness, and drowsiness, are also common. Less common but more serious side effects include gastrointestinal bleeding, peptic ulcers, cardiovascular events, renal impairment, and hepatotoxicity. Patients should be monitored closely for these adverse effects during therapy.
How should indomethacin be taken to minimize side effects? Indomethacin should be taken with food, milk, or an antacid to reduce gastrointestinal irritation. The medication should be taken at the lowest effective dose for the shortest possible duration. Patients should avoid alcohol while taking indomethacin, as alcohol can increase the risk of gastrointestinal bleeding. Adequate hydration should be maintained to reduce the risk of renal adverse effects.
Can indomethacin be used in elderly patients? Elderly patients are at increased risk of adverse effects from indomethacin, including gastrointestinal bleeding, central nervous system effects, renal impairment, and cardiovascular events. If indomethacin is necessary in an elderly patient, the lowest effective dose should be used, and the patient should be monitored closely for adverse effects. In many cases, alternative NSAIDs with more favorable safety profiles are preferred for elderly patients.
Is indomethacin safe for long-term use? The long-term use of indomethacin is limited by its adverse effect profile, particularly the risk of gastrointestinal ulcers and bleeding, which increases with duration of therapy. For chronic conditions requiring long-term NSAID therapy, other NSAIDs with more favorable safety profiles are generally preferred. When indomethacin is used for extended periods, patients should be monitored regularly for adverse effects, and the need for continued therapy should be reassessed periodically.
Can indomethacin be used during pregnancy? No, indomethacin should be avoided during pregnancy, particularly in the third trimester. The medication can cause premature closure of the ductus arteriosus in the fetus, impair fetal renal function, and inhibit uterine contractions. Indomethacin is specifically contraindicated after 32 to 34 weeks of gestation due to the risk of ductal closure. Women who are trying to conceive should also avoid indomethacin due to potential effects on ovulation.
What drug interactions are important with indomethacin? Indomethacin has significant interactions with many medications. It can increase the effects of anticoagulants (warfarin), increasing bleeding risk. It may reduce the effectiveness of blood pressure medications including ACE inhibitors, angiotensin receptor blockers, beta-blockers, and diuretics. It can increase lithium and methotrexate levels, potentially leading to toxicity. Concurrent use with other NSAIDs, including aspirin, should be avoided. Patients should provide their healthcare provider with a complete list of all medications they are taking, including over-the-counter drugs and supplements.