A white pill imprinted with “I 8” (or “I8”) most commonly identifies one of two distinct prescription medications, depending on its active ingredient and generic manufacturer:
- Ibuprofen 800 mg – White, capsule-shaped / oblong tablet imprinted with
I8. - Sevelamer Carbonate 800 mg – White, capsule-shaped / oblong tablet imprinted with
I 8.
Because both medications share the same shape, color, and 800 mg dosage unit, identifying the specific therapeutic purpose requires knowing which active drug you have.
Physical Visual Verification
Feature Option A: Ibuprofen Option B: Sevelamer Carbonate
- Imprint
I8–I 8(spaced) - Strength – 800 mg 800 mg
- Shape – Capsule-shaped / Oblong | Capsule-shaped / Oblong
- Primary Category Nonsteroidal Anti-Inflammatory Drug (NSAID) Phosphate Binder
- Pill Identification Warning: Always confirm unknown medications directly with a pharmacist or healthcare provider before consuming them. Never take a high-dose prescription pill unless it was explicitly prescribed to you.
Primary Identification A: Ibuprofen 800 mg
Overview & Mechanism of Action
Prescription-strength Ibuprofen 800 mg is a high-dose nonsteroidal anti-inflammatory drug (NSAID).
It acts as a non-selective inhibitor of the cyclooxygenase enzymes (COX-1 and COX-2). By blocking these enzymes, it suppresses the synthesis of prostaglandins—the local hormone-like lipid compounds responsible for mediating pain signals, fever, and localized tissue swelling.
Indications & Dosing
- Uses: Treatment of severe chronic joint pain (osteoarthritis, rheumatoid arthritis), acute musculoskeletal injury, severe dental pain, and primary dysmenorrhea.
- Adult Dosage: Typically 800 mg taken 3 to 4 times daily as needed.
- Maximum Daily Limit: Do not exceed 3,200 mg per day (four 800 mg tablets within 24 hours).
- Administration: Take with food or milk to minimize gastric upset.
Common & Serious Side Effects
- Common: Indigestion, heartburn, abdominal pain, nausea, diarrhea, and mild dizziness.
- Serious: Gastrointestinal bleeding (black/tarry stools, vomiting blood), acute kidney injury, severe fluid retention, and systemic allergic reactions.
Boxed Warnings & Key Precautions
- Cardiovascular Risk: NSAIDs increase the risk of serious thrombotic events, heart attack, and stroke, which can be fatal. Use is strictly contraindicated immediately before or after Coronary Artery Bypass Graft (CABG) surgery.
- Gastrointestinal Risk: High risk of severe stomach ulcers and bleeding without warning.
- Pregnancy Warning: Avoid taking ibuprofen starting at 20 weeks of pregnancy or later, as it can cause serious kidney and heart complications in the fetus.
Primary Identification B: Sevelamer Carbonate 800 mg
Overview & Mechanism of Action
- Sevelamer Carbonate 800 mg is a non-absorbed, metal-free phosphate binder.
Unlike NSAIDs, sevelamer is not absorbed into the bloodstream. It works locally within the gastrointestinal tract. Sevelamer consists of multiple amines separated by one carbon that become protonated in the stomach. These protonated amines bind to dietary phosphate ions from food in the intestine, preventing phosphate absorption and allowing it to be excreted safely through feces.
Indications & Dosing
- Uses: Control of serum phosphorus levels in adult and pediatric patients with chronic kidney disease (CKD) on dialysis (hyperphosphatemia).
- Adult Dosage: Standard starting dose is 800 mg to 1,600 mg taken three times daily with meals, titrated based on serum phosphorus levels.
- Administration: Must be taken with meals to effectively bind to dietary phosphorus. Swallow tablets whole; do not crush, chew, or break them.
Side Effects
- Common: Nausea, vomiting, diarrhea, dyspepsia, abdominal pain, flatulence, and constipation.
- Serious: Severe constipation, bowel obstruction, fecal impaction, and gastrointestinal perforation.
Precautions & Key Warnings
- Pre-existing GI Disorders: Contraindicated or used with extreme caution in patients with bowel obstruction or severe gastrointestinal motility disorders (e.g., severe constipation, dysphagia).
- Fat-Soluble Vitamin Deficiencies: Long-term use of sevelamer can reduce the absorption of fat-soluble vitamins (Vitamins A, D, E, and K) and folic acid.
- Drug Spacing: Sevelamer can bind to other oral medications, reducing their absorption. Other drugs (like ciprofloxacin, levothyroxine, or mycophenolate mofetil) should typically be taken 1 hour before or 3 hours after sevelamer.
Key Takeaways
- If prescribed for joint pain, severe sprains, or inflammation, you have Ibuprofen 800 mg.
- If prescribed for kidney disease or high blood phosphate, you have Sevelamer Carbonate 800 mg