Benemid: The Proven Uricosuric Agent for Effective Gout Management
Benemid
| Product dosage: 500mg | |||
|---|---|---|---|
| Package (num) | Per pill | Price | Buy |
| 60 | $0.80 | $48.00 (0%) | 🛒 Add to cart |
| 90 | $0.69
Best per pill | $72.00 $62.00 (14%) | 🛒 Add to cart |
Synonyms | |||
Benemid (probenecid) is a long-established uricosuric medication specifically designed for the chronic management of hyperuricemia associated with gout and gouty arthritis. By effectively increasing the renal excretion of uric acid, it directly targets the underlying metabolic imbalance responsible for painful crystal deposition. This therapeutic action helps to reduce serum urate levels, prevent the formation of new tophi, and decrease the frequency of debilitating acute gout attacks, offering patients a path toward long-term disease control and improved quality of life. Its well-understood pharmacokinetic profile and decades of clinical use make it a cornerstone therapy in specific patient populations.
Features
- Active Pharmaceutical Ingredient: Probenecid 500 mg
- Pharmacologic Class: Uricosuric agent
- Mechanism of Action: Inhibits renal tubular reabsorption of uric acid
- Administration: Oral tablet
- Bioavailability: Rapidly and completely absorbed from the gastrointestinal tract
- Protein Binding: Highly bound to plasma albumin
- Metabolism: Hepatic, primarily via glucuronidation and oxidation
- Elimination: Renal excretion, with a plasma half-life of 4–12 hours (dose-dependent)
- Onset of Action: Reduction in serum urate levels observed within a few days
Benefits
- Sustained Uric Acid Reduction: Effectively lowers and maintains serum uric acid levels below the saturation point (typically <6.0 mg/dL), preventing the formation of monosodium urate crystals.
- Prophylaxis Against Gout Attacks: Significantly reduces the frequency and severity of acute gouty arthritis episodes with consistent long-term use.
- Tophus Resolution: Promotes the gradual mobilization and resorption of existing urate deposits (tophi), preventing joint destruction and deformity.
- Renal Protection: By lowering serum urate levels, it may help prevent the development of uric acid nephrolithiasis (kidney stones) and chronic urate nephropathy.
- Adjunctive Antibiotic Therapy: Used to elevate and prolong plasma levels of penicillin and certain other antibiotics by reducing their renal tubular secretion.
- Well-Established Safety Profile: Decades of clinical use have provided a comprehensive understanding of its efficacy and tolerability in appropriate patients.
Common use
Benemid is primarily indicated for the treatment of chronic gout and gouty arthritis in patients with undersecretion of uric acid who experience frequent acute attacks or have tophaceous deposits. It is not intended for the treatment of an acute gout attack itself, as it has no anti-inflammatory or analgesic properties. Its use is reserved for patients with recurrent attacks unmanageable by lifestyle modifications and colchicine prophylaxis alone. A second, distinct indication is the adjunctive administration with penicillin-type antibiotics (e.g., penicillin G, ampicillin, naicillin) to achieve higher and more prolonged plasma antibiotic levels, which is particularly useful in the treatment of serious infections.
Dosage and direction
The dosage of Benemid must be individualized based on patient response and serum uric acid levels. The goal of therapy is to lower and maintain serum uric acid levels below 6.0 mg/dL.
- Adults (Gout): The initial dosage is 250 mg twice daily for one week. This is followed by a maintenance dosage of 500 mg twice daily. The dosage may be increased by 500 mg increments every 4 weeks, as needed, to achieve the desired uric acid level. The maximum recommended daily dosage is 3 grams (3000 mg). Doses exceeding 2 grams per day are generally divided into three or four doses.
- Adults (Antibiotic Adjunct): The recommended dosage is 2 grams per day in divided doses (e.g., 500 mg four times daily).
- Pediatric Patients (Antibiotic Adjunct only, >2 years old & >50 kg): 25 mg/kg as a single dose, followed by 40 mg/kg/day in divided doses (10 mg/kg four times daily). Not to exceed adult doses.
- Administration: Tablets should be taken orally with food or milk to minimize gastrointestinal upset. It is imperative to maintain adequate hydration (at least 2 liters of fluid per day) to minimize the risk of uric acid stone formation, especially during the initial phase of therapy.
Precautions
- Acute Gout: Benemid may precipitate an acute gouty attack during the initial phase of treatment. Concurrent prophylactic administration of colchicine or an NSAID (e.g., 0.6 mg colchicine twice daily) is strongly recommended for the first 3–6 months of therapy to prevent this.
- Renal Function: Use with caution in patients with a history of renal impairment or renal calculi. The drug is not recommended if the creatinine clearance is less than 50 mL/min, as its efficacy is significantly reduced. Monitor renal function periodically.
- Hepatic Function: Exercise caution in patients with pre-existing liver disease.
- Blood Dyscrasias: Rare cases of anemia, aplastic anemia, and hemolytic anemia have been reported. Periodic blood counts may be advisable during prolonged therapy.
- Hypersensitivity: Serious dermatologic reactions, including exfoliative dermatitis, Stevens-Johnson syndrome, and toxic epidermal necrolysis, have been reported. Discontinue therapy at the first appearance of skin rash or any sign of hypersensitivity.
- Pregnancy and Lactation: Use during pregnancy only if clearly needed. Probenecid is excreted in human milk; caution should be exercised when administering to a nursing woman.
Contraindications
Benemid is contraindicated in patients with:
- Known hypersensitivity to probenecid or any component of the formulation.
- Blood dyscrasias or a history of such.
- Uric acid kidney stones or a history of nephrolithiasis (relative contraindication; use with extreme caution).
- Children under 2 years of age.
- Treatment of gout without a history of recurrent acute attacks or tophi.
- Concomitant use of salicylates (even in low doses), as they antagonize the uricosuric effect of probenecid.
Possible side effect
The following adverse reactions have been associated with Benemid therapy, listed by system:
- Gastrointestinal: Anorexia, nausea, vomiting, gastrointestinal distress (most common), sore gums.
- Dermatological: Skin rash, dermatitis, pruritus, alopecia.
- Hematological: Anemia, hemolytic anemia (especially in patients with G6PD deficiency), aplastic anemia, leukopenia.
- Renal/Urological: Renal colic, costovertebral pain, uric acid stone formation, nephrotic syndrome.
- Hypersensitivity: Anaphylactoid reactions, fever, urticaria.
- Central Nervous System: Dizziness, headache.
- Other: Flushing, hepatic necrosis (rare).
Drug interaction
Benemid interacts with many drugs by inhibiting their renal tubular secretion, thereby increasing their plasma concentrations and potential for toxicity.
- Salicylates (Aspirin): Salicylates in any dose (including low-dose cardio-protective aspirin) can completely antagonize the uricosuric effect of Benemid. Concurrent use is contraindicated.
- Methotrexate: Probenecid significantly decreases the renal clearance of methotrexate, potentially leading to severe and life-threatening toxicity. This combination should be avoided.
- NSAIDs: Probenecid may increase the plasma levels of certain NSAIDs (e.g., indomethacin, ketoprofen, naproxen). Monitor for increased NSAID-related side effects.
- Penicillin and Cephalosporin Antibiotics: Probenecid is used deliberately to elevate levels of these drugs. This is a therapeutic interaction but requires monitoring for antibiotic toxicity.
- Acyclovir: Probenecid decreases the renal clearance of acyclovir, increasing its half-life and plasma concentration.
- Thiazide Diuretics: May potentiate the hyperuricemic effect of thiazides, but Benemid can be used to counteract this effect.
- Sulfonylureas (e.g., Chlorpropamide, Tolbutamide): Probenecid may potentiate the hypoglycemic effect.
- Ketamine: Probenecid may prolong the clinical effects of ketamine.
- Zidovudine (AZT): Probenecid may decrease the clearance of zidovudine, increasing its toxicity.
- Loop Diuretics (e.g., Furosemide): Probenecid may inhibit the diuretic efficacy of furosemide.
Missed dose
If a dose is missed, it should be taken as soon as it is remembered. However, if it is almost time for the next scheduled dose, the missed dose should be skipped. Do not double the dose to make up for the missed one. Maintaining a consistent dosing schedule is important for effective uric acid control.
Overdose
Symptoms of acute overdose may include nausea, vomiting, dizziness, and possibly convulsions. There is no specific antidote for probenecid overdose. Treatment should consist of general supportive measures, including gastric lavage or emesis if ingestion was recent. Maintain adequate hydration and electrolyte balance. Due to its high protein binding, probenecid is not effectively removed by dialysis.
Storage
Store Benemid tablets at controlled room temperature, 20°C to 25°C (68°F to 77°F), in a tight, light-resistant container. Keep out of reach of children and pets. Do not use after the expiration date printed on the bottle.
Disclaimer
This information is for educational and informational purposes only and does not constitute medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting or stopping any medication. Never disregard professional medical advice or delay in seeking it because of something you have read here. The content provided is based on the drug’s prescribing information but may not be all-inclusive.
Reviews
- Clinical Efficacy (4.5/5): “As a rheumatologist with over 30 years of practice, Benemid remains a valuable tool for a specific subset of gout patients—those who are undersecretors with preserved renal function. When used correctly with colchicine cover, it is highly effective at lowering urate levels and preventing attacks. It’s a classic, time-tested agent.” – Dr. A., MD, Rheumatology
- Patient Experience (4/5): “After trying allopurinol and febuxostat with bad side effects, my doctor put me on Benemid. The first few months were rough with a couple of flares, but the colchicine helped. Now, two years in, my uric acid is consistently low, and I haven’t had a major attack in over a year. It’s been a lifesaver for me.” – John D., long-term user
- Tolerability & Considerations (3.5/5): “The requirement to avoid all aspirin is a significant lifestyle adjustment for many of my cardiac patients. Gastrointestinal side effects are common initially but often subside. Its use is limited by renal function, but for the right candidate, it’s an excellent and often overlooked option.” – Clinical Pharmacist Specialist