Benemid (probenecid) is a uricosuric agent prescribed for the management of chronic gout and gouty arthritis. It functions by increasing the urinary excretion of uric acid, thereby reducing serum urate levels and preventing the formation of urate crystals. This medication is indicated for patients who experience frequent gout attacks and have not achieved adequate control through lifestyle modifications or other therapies alone. Proper use under medical supervision can significantly reduce the incidence of painful flares and long-term joint damage.

Features

• Active ingredient: Probenecid
• Mechanism: Uricosuric agent that inhibits renal tubular reabsorption of uric acid
• Formulation: Oral tablets, typically 500 mg
• Prescription-only medication
• Often used in combination with a colchicine or NSAID during initial therapy to prevent acute flares

Benefits

• Effectively lowers serum uric acid levels to sub-saturation points, preventing crystal formation
• Reduces the frequency and severity of acute gout attacks with long-term use
• May help resolve existing tophi and prevent new tophi development
• Allows for decreased reliance on acute flare medications when used prophylactically
• Can be used as an adjunct to antibiotic therapy to elevate and prolong antibiotic plasma levels
• Helps prevent long-term joint damage and chronic arthropathy associated with uncontrolled hyperuricemia

Common use

Benemid is primarily indicated for the treatment of hyperuricemia associated with gout and gouty arthritis. It is particularly suitable for patients with relatively underexcreting gout, where urinary uric acid excretion is less than 800 mg/day on a general diet. The medication is not intended for the treatment of acute gout attacks but rather for prophylaxis against recurrent episodes. Additionally, Benemid is used in combination with penicillin-class antibiotics to elevate and prolong antibiotic plasma concentrations by reducing renal tubular secretion of these agents.

Dosage and direction

The initial adult dosage for gout management is 250 mg twice daily for one week, followed by 500 mg twice daily. Dosage may be increased by 500 mg every 4 weeks as needed, with maintenance doses typically ranging from 1-2 grams daily divided into two doses. The maximum recommended daily dose is 3 grams. Doses exceeding 2 grams per day should be divided into three or four administrations. For antibiotic potentiation, adults typically receive 2 grams daily in divided doses. Administration should be accompanied by adequate fluid intake (minimum 2 liters daily) to minimize risk of uric acid stone formation. Tablets should be taken with food or milk to reduce gastrointestinal discomfort.

Precautions

Regular monitoring of serum uric acid levels is recommended to assess therapeutic response. Renal function should be evaluated periodically, as diminished effectiveness may occur in patients with renal impairment. Patients should maintain adequate hydration (at least 2 liters of fluid daily) to prevent uric acid nephrolithiasis. Use with caution in patients with history of peptic ulcer disease. Blood counts may be advised during prolonged therapy. Benemid may precipitate acute gouty attacks during initial treatment; concurrent administration of colchicine or NSAIDs is often recommended during the first 3-6 months of therapy. Not recommended for treatment of asymptomatic hyperuricemia.

Contraindications

Hypersensitivity to probenecid or any component of the formulation; blood dyscrasias; uric acid kidney stones; during acute gout attack (initiation); children under 2 years of age; patients with creatinine clearance less than 30 mL/min. Not recommended for patients with known hypersensitivity to sulfonamides. Contraindicated in patients with history of blood dyscrasias or uric acid kidney stones. Should not be administered concurrently with salicylates in doses greater than 1-2 grams daily as they antagonize uricosuric effect.

Possible side effect

Common adverse reactions include gastrointestinal disturbances (nausea, vomiting, loss of appetite), headache, dizziness, and increased urinary frequency. Less frequently reported effects include flushing, sore gums, anemia, and hematuria. Hypersensitivity reactions may occur, including dermatitis, pruritus, and fever. Rare but serious adverse effects include nephrotic syndrome, hepatic necrosis, and aplastic anemia. Uric acid stones may form, particularly during initial therapy without adequate hydration. Acute gouty attacks may occur during initial treatment period.

Drug interaction

Salicylates (including low-dose aspirin) antagonize uricosuric effect and should be avoided. Benemid may increase plasma levels of NSAIDs, sulfonylureas, oral anticoagulants, rifampin, and dapsone. It prolongs half-life of penicillin and cephalosporin antibiotics. May decrease hepatic excretion of methotrexate. Concurrent use with pyrazinamide may diminish uricosuric effect. Thiazide diuretics may decrease effectiveness of Benemid. Allopurinol may be used concomitantly for enhanced urate-lowering effect.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is almost time for the next scheduled dose. In that case, skip the missed dose and resume the regular dosing schedule. Do not double the dose to make up for a missed administration. Consistent daily dosing is important for maintaining stable uric acid levels. Patients should contact their healthcare provider if multiple doses are missed or if unsure about how to resume therapy.

Overdose

Symptoms of overdose may include nausea, vomiting, dizziness, and convulsions. There is no specific antidote for probenecid overdose. Treatment should be supportive and symptomatic, including gastric lavage or activated charcoal if ingestion was recent. Maintain adequate hydration and urinary output to promote excretion. Hemodialysis may be considered in severe cases, though probenecid is highly protein-bound which may limit dialysis effectiveness. Monitor renal function and electrolyte status in cases of significant overdose.

Storage

Store at controlled room temperature (20-25°C or 68-77°F) in a tightly closed container. Protect from light and moisture. Keep out of reach of children and pets. Do not use after expiration date printed on packaging. Do not transfer tablets to other containers that may not provide adequate protection from moisture or light. Discard any medication that appears discolored or shows signs of deterioration.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Benemid is a prescription medication that should be used only under the supervision of a qualified healthcare professional. Individual response to therapy may vary. Patients should not adjust dosage or discontinue medication without consulting their physician. The complete prescribing information should be reviewed before initiating therapy. Only a healthcare provider can determine if this medication is appropriate for a particular patient based on their medical history and current condition.

Reviews

“After struggling with frequent gout attacks for years, Benemid has significantly reduced my flare-ups. The first few months required careful management with colchicine, but now I’m down to maybe one mild episode per year instead of monthly severe attacks.” - Michael T., 54

“As a rheumatologist, I find Benemid remains a valuable option for appropriate patients with underexcreting gout. It’s particularly useful when patients cannot tolerate allopurinol or require combination therapy. The need for adequate hydration and avoidance of salicylates requires careful patient education.” - Dr. Eleanor J., Rheumatologist

“The initial adjustment period was challenging with some gastrointestinal discomfort, but with dose titration and taking with food, these effects diminished. My uric acid levels have remained consistently below 6.0 mg/dL for over two years now.” - Robert L., 61

“I prescribe Benemid selectively for patients with good renal function who have difficulty with xanthine oxidase inhibitors. It’s effective when used properly, though requires more monitoring than some newer agents. The antibiotic-potentiating effect can be clinically useful in certain situations.” - Dr. William K., Infectious Disease Specialist