The white pill stamped with “IP 466” is a high-potency, prescription-strength formulation of Ibuprofen 800 mg. Manufactured primarily by Amneal Pharmaceuticals (and formerly Interpharm), it belongs to the class of medications known as nonsteroidal anti-inflammatory drugs (NSAIDs).
Pill Identification
Physical Property – Specification
- Active Ingredient – Ibuprofen (800 mg)
- Imprint Code –
IP 466(obverse), Plain (reverse) - Color – White
- Shape – Capsule-shaped / Oblong (biconvex)
- Coating – Aqueous film-coated
- Drug Class – Nonsteroidal Anti-inflammatory Drug (NSAID)
- Prescription Status – Rx-only (over-the-counter ibuprofen is capped at 200 mg per tablet)
Mechanism of Action
Ibuprofen functions as a non-selective inhibitor of the cyclooxygenase (COX) enzymes, specifically COX-1 and COX-2:
- Prostaglandin Inhibition: Cyclooxygenase enzymes convert arachidonic acid into pro-inflammatory prostaglandins. By blocking COX-1 and COX-2, ibuprofen suppresses the synthesis of prostaglandins in peripheral tissues.
- Analgesic & Anti-Inflammatory Effects: Prostaglandins sensitize pain receptors to chemical mediators (such as bradykinin) and promote vasodilation and tissue edema. Reducing prostaglandin levels decreases inflammatory swelling, joint stiffness, and nociceptive pain signals sent to the brain.
- Antipyretic Effect: Ibuprofen acts on the hypothalamus to reduce fever by lowering elevated central thermal set-points driven by pyrogenic cytokines.
Indications & Dosage
Because 800 mg is the highest single oral tablet strength of ibuprofen available, it is indicated for conditions requiring intense anti-inflammatory or analgesic therapy under medical supervision.
Primary Indications
- Rheumatoid Arthritis & Osteoarthritis: Chronic management of joint pain, swelling, and inflammation.
- Mild-to-Moderate Severe Pain: Acute relief from post-surgical pain, severe dental procedures, or musculoskeletal trauma.
- Primary Dysmenorrhea: Severe menstrual cramps and pain.
Dosage & Administration
- Standard Adult Dosing: Typically 800 mg taken orally 3 to 4 times daily as needed (every 6 to 8 hours).
- Maximum Daily Limit: 3,200 mg in a 24-hour period (equivalent to 4 of the IP 466 tablets).
- Administration Tip: Take with food, milk, or an antacid to reduce direct gastric lining irritation.
Side Effects
Common Side Effects
- Gastrointestinal: Heartburn, dyspepsia, stomach cramps, nausea, flatulence, diarrhea, or constipation.
- Central Nervous System: Dizziness, mild headache, nervousness, or drowsiness.
- Fluid Balance: Mild fluid retention or swelling in the lower extremities (edema).
Serious Side Effects
- Severe GI Bleeding & Ulcers: Dark tarry stools, coffee-ground vomit, or persistent abdominal pain.
- Renal Toxicity: Decreased urination, fluid accumulation, acute kidney injury, or elevated serum creatinine.
- Cardiovascular Events: Chest pain, shortness of breath, sudden weakness or numbness on one side of the body, or slurred speech.
- Hepatotoxicity: Yellowing of the eyes/skin (jaundice), dark urine, or severe fatigue.
- Severe Skin Reactions: Stevens-Johnson Syndrome (SJS) or Toxic Epidermal Necrolysis (TEN) manifesting as progressive skin rash, blistering, or peeling.
Boxed Warnings & Key Safety Warnings
FDA Black Box Warnings
- Cardiovascular Thrombotic Risk: NSAIDs cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction (heart attack) and stroke, which can be fatal. This risk increases with higher doses (such as 800 mg) and longer duration of use. Contraindicated for perioperative pain in Coronary Artery Bypass Graft (CABG) surgery.
- Gastrointestinal Bleeding, Ulceration, & Perforation: NSAIDs increase the risk of serious gastrointestinal adverse events, including bleeding, ulceration, and stomach or intestinal perforation, which can occur at any time without warning symptoms. Elderly patients and those with a history of peptic ulcer disease are at higher risk.
Precautions & Drug Interactions
Precautions
- Pregnancy: Avoid starting at 20 weeks of gestation or later. NSAIDs used during the second half of pregnancy can cause fetal renal dysfunction leading to oligohydramnios (low amniotic fluid) and premature closure of the fetal ductus arteriosus.
- Pre-existing Conditions: Exercise extreme caution if you have uncontrolled hypertension, congestive heart failure, chronic kidney disease, active stomach ulcers, or severe hepatic impairment.
- Asthma: Patients with aspirin-sensitive asthma may experience severe, life-threatening bronchospasm when taking NSAIDs.
Significant Drug Interactions
- Anticoagulants & Antiplatelets (e.g., Warfarin, Aspirin, Clopidogrel): Dramatically increases the risk of major gastrointestinal and systemic bleeding.
- Antihypertensives (ACE Inhibitors, ARBs, Beta-Blockers, Diuretics): Ibuprofen can blunt the blood-pressure-lowering effects of these agents and worsen renal function when combined with diuretics and ACE inhibitors (“triple whammy” acute kidney injury risk).
- Lithium & Methotrexate: Ibuprofen reduces renal clearance of these medications, raising their serum levels to toxic ranges.
- SSRIs / SNRIs: Combined use increases the risk of upper gastrointestinal ulceration and bleeding.