Generic Benemid (Probenecid)

Introduction

Benemid is a pharmaceutical product whose active ingredient is probenecid. It is supplied as a 500 mg oral tablet and belongs to the class of uricosuric agents. The primary, FDA-approved purpose of probenecid is to lower serum uric acid levels in patients with gout by increasing renal excretion of uric acid. In addition, probenecid is approved as an adjunct to certain antibiotics (e.g., penicillins, cephalosporins) to prolong their plasma concentrations, thereby enhancing antimicrobial efficacy. The medication is manufactured by several international firms and distributed in generic form worldwide.

What is Benemid?

Benemid is the generic version of well-known medications, containing the active compound probenecid. Our online pharmacy provides this generic alternative as a cost-effective treatment option. Probenecid was first synthesized in the s and introduced for clinical use in the early s as one of the first uricosuric drugs. It is chemically a benzoic-acid derivative that interferes with renal tubular reabsorption of uric acid. The product is marketed under brand names such as Benemid, Prouric, and Uricult in various countries, all of which contain the same 500 mg tablet formulation.

How Benemid Works

Probenecid acts primarily on the proximal renal tubule. It blocks the organic anion transporter 1 (OAT1) and related urate-transport proteins, reducing the reabsorption of uric acid back into the bloodstream. The resulting increase in urinary uric acid excretion lowers the serum concentration, which alleviates gout flares and prevents crystal deposition in joints.

When co-administered with β-lactam antibiotics, probenecid competitively inhibits OAT1-mediated tubular secretion of the antibiotic. This inhibition slows renal clearance, prolonging the drug’s half-life and maintaining therapeutic plasma levels for a longer period. The onset of uric-lowering action typically occurs within 2-3 days, while the effect on antibiotic pharmacokinetics is evident after a single dose. Probenecid is eliminated unchanged in the urine; renal function therefore influences both efficacy and safety.

Conditions Treated with Benemid

• Gout (hyperuricemia) - By increasing urinary uric acid excretion, probenecid reduces serum urate concentrations, preventing acute gout attacks and slowing disease progression.
• Adjunctive therapy with β-lactam antibiotics - Approved to extend the plasma half-life of agents such as ampicillin, amoxicillin, and ceftriaxone, allowing less frequent dosing or higher effective concentrations.

These indications are supported by regulatory reviews from the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Clinical guidelines (e.g., ACR 202 gout management) recommend uricosurics like probenecid for patients who either cannot tolerate xanthine oxidase inhibitors or require additional urate-lowering capacity.

Off-Label and Investigational Uses of Benemid

• Prevention of calcium-oxalate kidney stones - Small clinical series have reported that probenecid-induced uricosuria may reduce stone formation in patients with hyperuricosuric stone disease. Evidence remains limited and the indication is not formally approved.
• Adjunct in certain antiviral regimens - In vitro studies suggest that probenecid can inhibit the renal clearance of some antivirals, potentially enhancing exposure. Human trials are ongoing, and safety data are not yet definitive.
• Management of hyperuricemia secondary to chemotherapy - Oncologists occasionally add probenecid to control urate spikes during tumor lysis syndrome, although standard care usually favours rasburicase or allopurinol.

These applications are not approved by regulatory agencies. Patients should discuss any off-label consideration only with a qualified healthcare professional, as the balance of benefit versus risk has not been formally established.

Is Benemid the Right Medication for You?

Benemid is most appropriate for adults with:

• Documented hyperuricemia or recurrent gout attacks who have an adequate renal function (eGFR ≥ 30 mL/min/1.73 m²).
• A clinical need to maintain higher plasma levels of penicillins or cephalosporins, such as for certain infections requiring prolonged antibiotic exposure.

Contraindications include:

• Severe renal impairment (eGFR < 30 mL/min/1.73 m²).
• Known hypersensitivity to probenecid or any tablet excipients.
• Active uric acid kidney stones, as increased uricosuria may exacerbate stone formation.

Patients with a history of hemolytic anemia, especially those with glucose-6-phosphate dehydrogenase deficiency, should avoid probenecid because of the risk of hemolysis.

Risks, Side Effects, and Interactions

Common

• Gastrointestinal discomfort (nausea, abdominal pain, dyspepsia)
• Headache
• Dizziness

Rare

• Allergic skin reactions (rash, pruritus)
• Photosensitivity
• Elevated liver enzymes

Serious

• Severe hypersensitivity reactions (Stevens-Johnson syndrome, anaphylaxis) - seek emergency care.
• Hemolytic anemia, particularly in G6PD-deficient individuals.
• Nephrolithiasis (uric acid kidney stones) - monitor urine output and stay well hydrated.

Drug-Drug Interactions

• β-lactam antibiotics - intentional interaction (dose-sparing effect).
• Non-steroidal anti-inflammatory drugs (NSAIDs) - may reduce renal clearance of probenecid, increasing uricosuric effect and stone risk.
• Azathioprine, mercaptopurine - probenecid can raise plasma levels, heightening toxicity; dose adjustment may be required.
• Methotrexate - reduced renal excretion may increase toxicity.

Drug-Food Interactions

• High-purine foods (red meat, organ meats, certain seafood) can counteract uric-lowering benefits; moderation is advised.
• Alcohol, especially beer, increases uric acid production and should be limited.

Use: Dosing, Missed Dose, Overdose

Standard dosing for gout: 500 mg orally once daily; the dose may be increased to 100 mg (two tablets) once daily if serum urate goals are not met after 2-4 weeks, provided renal function permits.

Adjunctive antibiotic dosing: Typically 500 mg taken 1-2 hours before or after the β-lactam antibiotic, not exceeding 2 g per day.

Missed dose: Take the missed tablet as soon as remembered unless it is within 12 hours of the next scheduled dose; then skip the missed dose and resume the regular schedule. Do not double-dose.

Overdose: Symptoms may include severe nausea, vomiting, dizziness, and renal dysfunction. Immediate medical attention is required; supportive care and gastric lavage are standard measures.

Administration tips - Benemid tablets can be taken with or without food; however, a full glass of water is recommended to lessen kidney stone risk. Avoid concurrent alcohol consumption, and refrain from operating heavy machinery if dizziness occurs.

FAQ

• What should I know about storing Benemid tablets? Store the tablets in a cool, dry place below 25 °C (77 °F). Keep them out of reach of children and do not refrigerate unless instructed by a pharmacist.

• Can I travel internationally with Benemid? Yes, but keep the medication in its original packaging with a copy of the prescription or a pharmacist’s label. Some countries require a medical certificate for import; verify local regulations before departure.

• How does Benemid appear compared to brand-name versions? Generic 500 mg tablets are typically round, white to off-white, and may be scored for splitting. Imprint codes vary by manufacturer but are listed on the product label.

• Are there any inactive ingredients that could cause an allergy? Common excipients include lactose, magnesium stearate, and microcrystalline cellulose. Patients with lactose intolerance or known sensitivities should check the specific product’s ingredient list.

• Does Benemid affect urine drug testing? Probenecid does not usually cause false-positive results on standard narcotic or cannabis screenings, but it can alter the pharmacokinetics of certain drugs, potentially affecting detection windows for some medications.

• Is Benemid safe for people with liver disease? Probenecid is minimally metabolized by the liver, so mild to moderate hepatic impairment generally does not require dose adjustment. Severe liver disease should be evaluated by a clinician before use.

• Can hydration reduce the risk of kidney stones while taking Benemid? Adequate fluid intake (≥ 2 L of water daily) helps dilute urinary uric acid, lowering stone formation risk. Patients are advised to maintain consistent hydration throughout the day.

• What is the difference between Benemid and allopurinol? Benemid increases uric acid excretion (uricosuric), whereas allopurinol decreases uric acid production by inhibiting xanthine oxidase. Choice depends on renal function, previous drug response, and physician assessment.

• Does Benemid interact with over-the-counter supplements? Vitamin C at high doses can modestly increase urinary uric acid excretion, potentially augmenting Benemid’s effect. However, large amounts of vitamin C may also raise stone risk; discuss supplement use with a healthcare professional.

• How long before a surgical procedure should Benemid be stopped? Because probenecid can affect renal handling of certain antibiotics used for prophylaxis, it is usually withheld 24 hours before major surgery. Follow the peri-operative instructions provided by the surgical team.

• Can Benemid be crushed or split for dose adjustment? If the tablet is scored, it may be split in half to achieve a 250 mg dose under clinician guidance. Crushing is not recommended unless a liquid formulation is unavailable, as it may affect absorption.

Glossary

Uricosuric

A class of drugs that increase the excretion of uric acid in the urine, thereby lowering serum urate levels.

Organic Anion Transporter 1 (OAT1)

A protein in the renal proximal tubule responsible for moving organic anions, including uric acid and certain drugs, from the blood into the urine.

Hyperuricemia

An abnormally high concentration of uric acid in the blood, often a precursor to gout attacks.

Adjunctive therapy

An additional treatment used together with a primary medication to enhance its effectiveness or reduce side effects.

Buying Benemid from Our Online pharmacy

Benemid can be purchased conveniently from our online pharmacy. Our service offers a price that closely matches the manufacturer’s cost, making the medication more affordable for patients who face high out-of-pocket expenses. All tablets are sourced from licensed, verified suppliers who meet stringent quality-control standards, ensuring that each batch is authentic and pharmaceutically sound.

Delivery is discreet and reliable: standard airmail typically arrives within three weeks, while express shipping is available in about seven days for those who need the medication sooner. Because we operate as a pharmacy-broker service, we can obtain international formulations that may not be stocked locally, providing a practical solution for patients with limited access through conventional pharmacies.

Privacy is a core principle of our operation. Orders are packaged without external labeling, and all personal information is handled in compliance with applicable data-protection regulations. By choosing our online pharmacy, patients gain a secure, cost-effective pathway to obtain Benemid without compromising confidentiality or quality.

Disclaimer

The information presented about Benemid is intended for general educational purposes and does not substitute professional medical advice. Treatment choices, including any off-label applications, should be undertaken only under the supervision of a qualified healthcare provider. Readers are assumed to be responsible adults capable of making informed health decisions. Our online pharmacy provides access to Benemid for individuals who may encounter limited availability through conventional pharmacies or who are seeking affordable generic alternatives. Always consult a qualified clinician before initiating, altering, or discontinuing any medication.