Indomet SR is a sustained-release (SR) capsule containing Indomethacin BP 75 mg. It is manufactured by Opsonin Pharma Ltd. in Bangladesh.

Indications:

Indomet SR is a nonsteroidal anti-inflammatory drug (NSAID) primarily used for its anti-inflammatory, analgesic (pain-relieving), and antipyretic (fever-reducing) properties. The sustained-release formulation aims to provide prolonged relief and reduce dosing frequency. It is indicated for the treatment of various inflammatory and rheumatic disorders, including:

• Rheumatoid Arthritis
• Ankylosing Spondylitis
• Osteoarthritis (degenerative joint disease)
• Acute Gouty Arthritis
• Acute non-articular rheumatism (e.g., bursitis, synovitis, tendinitis)

Pharmacology:

Indomethacin works by potently inhibiting cyclooxygenase (COX) enzymes, particularly COX-1 and COX-2. This action reduces the synthesis of prostaglandins, which are key mediators of pain, inflammation, and fever in the body. Its effect is not related to the pituitary gland or the adrenals. Indomethacin is well absorbed after oral administration, with peak plasma levels typically occurring within 2 hours for immediate-release forms. The sustained-release form ensures a prolonged therapeutic effect. About 90% of a single dose is eliminated within 24-48 hours, mainly through urine and feces.

Dosage and Administration:

Indomet SR 75 mg capsule is typically taken orally. It should be taken with food, milk, or an antacid to minimize gastrointestinal disturbances.

• For Rheumatoid Arthritis, Ankylosing Spondylitis, and Osteoarthritis:
  • The initial dose is 75 mg (one capsule) once daily.
  • If symptoms are severe, 75 mg twice daily may be required.
• For Acute attacks of gout:
  • May be controlled with a dose of 75 mg twice daily.
• For Acute non-articular rheumatism (bursitis, synovitis, tendinitis):
  • 1 to 2 sustained-release capsules daily depending on the severity of the case.

Contraindications:

Indomet SR is contraindicated in patients with:

• Known hypersensitivity to indomethacin, aspirin, or other NSAIDs.
• Active peptic ulcer, gastritis, or active ulcerative colitis. It should be used with caution in patients with a history of these disorders (in such cases, suppositories might be preferred if available and indicated).
• Previously hypersensitive patients to the drug.
• In the setting of coronary artery bypass graft (CABG) surgery.
• Patients with psychiatric problems, epilepsy, or Parkinsonism, as the drug may aggravate these conditions (use with caution).
• Severe renal or hepatic impairment.

Side Effects:

Common side effects include:

• Headaches (often in the morning) and mild vertigo, especially during the early weeks of therapy (these are often transient).
• Gastrointestinal reactions: Nausea, vomiting, diarrhea, epigastric and abdominal pain. These are often dose-related and may subside with dose reduction or by taking the capsule immediately after meals with an antacid.
• Drowsiness, dizziness.
• Increased creatine level in blood.

Serious (but less common) side effects can include:

• Gastrointestinal bleeding, ulceration, or perforation.
• Increased risk of serious cardiovascular thrombotic events, including myocardial infarction (heart attack) and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use. 
• Fluid retention (edema) and heart failure.
• Kidney damage.
• Severe skin reactions (e.g., Stevens-Johnson syndrome).
• Anemia.
• Tinnitus (ringing in the ears).

Precautions and Warnings:

• Gastrointestinal Risk: NSAIDs can cause serious gastrointestinal adverse events (bleeding, ulceration, perforation) that can be fatal. This risk can occur at any time without warning symptoms.
• Cardiovascular Risk: NSAIDs increase the risk of serious cardiovascular thrombotic events. Avoid use in patients with a recent myocardial infarction unless benefits outweigh risks. It is contraindicated for peri-operative pain in CABG surgery.
• Renal/Hepatic Impairment: Use with caution; monitor kidney and liver function regularly, especially during long-term treatment.
• Fluid Retention: Use with caution in patients with fluid retention, hypertension, or heart failure.
• Psychiatric/Neurological Conditions: Use with caution in patients with psychiatric problems, epilepsy, or Parkinsonism.
• Alcohol: Avoid alcohol consumption as it can cause excessive drowsiness and increase the risk of stomach problems.
• Driving/Operating Machinery: May decrease alertness, affect vision, or cause dizziness/sleepiness. Exercise caution.
• Long-term use: Long-term use may lead to serious complications like stomach bleeding and kidney problems; regular monitoring is advised.

Pregnancy and Lactation:

• Pregnancy: Indomet SR is generally not recommended for pregnant women due to insufficient clinical studies and definite evidence of risk to the developing baby, particularly in the third trimester (e.g., premature closure of the ductus arteriosus).
• Lactation: Indomet SR is probably unsafe to use during breastfeeding, as limited human data suggests the drug may pass into breast milk and harm the baby.

Drug Interactions:

• Anticoagulants (e.g., Warfarin): Increased risk of GI bleeding.
• Lithium: May increase lithium plasma levels, leading to toxicity.
• Diuretics and Antihypertensive drugs (e.g., Beta-blockers, ACE inhibitors): May reduce their effectiveness.
• Diflunisal: Concurrent use is not recommended due to increased indomethacin levels and risk of fatal GI hemorrhage.
• Aspirin: Increases risk of GI side effects.
• Probenecid: May increase indomethacin plasma levels.
• Sulfonylureas: May enhance their hypoglycemic effect.
• Methotrexate: May increase methotrexate levels and toxicity.

Storage Conditions:

Store in a cool and dry place, protected from light. Keep out of the reach of children.

Note: This information is for general knowledge and informational purposes only and does not substitute professional medical advice. Always consult your doctor or pharmacist for specific instructions and guidance regarding your medication.