Indomethacin

What is Indomethacin?

Indomethacin is a nonsteroidal anti-inflammatory drug (NSAID) that reduces pain, inflammation, and fever. It belongs to the indole acetic acid class of NSAIDs and is considered one of the more potent anti-inflammatory medications available. Indomethacin is prescribed for various inflammatory conditions and is also used in specific medical procedures due to its unique properties.

Uses

Indomethacin is approved for several medical conditions:

• Rheumatoid arthritis: Reduces joint inflammation, pain, and stiffness associated with this autoimmune condition
• Osteoarthritis: Helps manage pain and inflammation in degenerative joint disease
• Ankylosing spondylitis: Treats inflammation of the spine and sacroiliac joints
• Patent ductus arteriosus: Used intravenously in premature infants to help close this heart condition
• Gout attacks: Provides rapid relief from acute gouty arthritis episodes
• Bursitis and tendinitis: Reduces inflammation in soft tissues around joints

How it works

Indomethacin works by blocking cyclooxygenase (COX) enzymes, specifically COX-1 and COX-2, which are responsible for producing prostaglandins. Prostaglandins are chemical messengers that promote inflammation, pain, and fever throughout the body. By inhibiting these enzymes, indomethacin reduces the production of inflammatory prostaglandins, thereby decreasing pain, swelling, and inflammation at the affected sites.

Side effects

Common side effects include:

Submit Your Paper

• Headache and dizziness
• Nausea and stomach upset
• Heartburn and indigestion
• Drowsiness and fatigue
• Diarrhea or constipation
• Fluid retention and swelling
• Mild skin rash
• Ringing in the ears (tinnitus)

Serious side effects requiring immediate medical attention:

• Severe stomach bleeding or ulceration
• Heart attack or stroke symptoms
• Severe allergic reactions with difficulty breathing
• Liver damage with yellowing of skin or eyes
• Kidney problems with decreased urination or swelling

Warnings and precautions

• Cardiovascular risk: Indomethacin may increase the risk of heart attack and stroke, especially with long-term use or in people with existing heart disease
• Gastrointestinal bleeding: This medication carries a significant risk of stomach ulcers and bleeding, particularly in elderly patients or those with a history of peptic ulcer disease
• Pregnancy considerations: Indomethacin should be avoided during the third trimester of pregnancy as it may cause premature closure of the ductus arteriosus in the fetus
• Kidney and liver function: Patients with kidney or liver disease require careful monitoring and possible dose adjustments
• Central nervous system effects: Indomethacin may cause more CNS side effects than other NSAIDs, including confusion and depression, especially in elderly patients

Interactions

Indomethacin interacts with numerous medications and substances:

• Blood thinners (warfarin): Increases bleeding risk by enhancing anticoagulant effects
• ACE inhibitors and ARBs: May reduce blood pressure-lowering effects and increase kidney damage risk
• Diuretics: Can decrease diuretic effectiveness and worsen kidney function
• Lithium: Increases lithium blood levels, potentially causing toxicity
• Methotrexate: Enhances methotrexate toxicity by reducing its elimination
• Digoxin: May increase digoxin levels in the blood
• Other NSAIDs and aspirin: Increases risk of stomach bleeding and kidney problems
• Alcohol: Significantly increases risk of gastrointestinal bleeding

Check interactions with the GMJ Interaction Checker

Dosage

Typical adult dosages vary by condition:

• Rheumatoid arthritis/Osteoarthritis: 25-50 mg two to three times daily, with a maximum of 200 mg per day
• Acute gout: 50 mg three times daily until pain subsides, usually 3-5 days
• Ankylosing spondylitis: 25 mg two to three times daily, may increase to 50 mg three times daily if needed

Extended-release capsules are typically taken once or twice daily. The lowest effective dose should be used for the shortest duration necessary. Always follow your healthcare provider’s specific dosing instructions, as individual needs may vary based on condition severity, response to treatment, and other health factors.

Sources: FDA DailyMed drug labels (public domain), BNF, WHO Essential Medicines List. This article is for informational purposes only and does not constitute medical advice. Always consult your healthcare provider before starting or stopping any medication.

This work is licensed under Creative Commons Attribution 4.0 International (CC BY 4.0). You are free to share and adapt this content with attribution to GMJ News (news.gmj.ge).