Probenecid Medications

Probenecid is a uricosuric and renal tubular secretion inhibitor that enhances uric acid elimination by the kidneys. It is indicated for the treatment of gout and as an adjunct in antibiotic therapy.

Benemid

Probenecid

$0.76 per pill

500mg

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Probenecid Information

Probenecid is a uricosuric medication primarily prescribed to lower elevated serum uric acid in adults with gout or chronic hyperuricemia. Belonging to the class of renal tubular secretion inhibitors, it works by blocking the reabsorption of uric acid in the proximal tubule, thereby increasing urinary excretion. First approved by the U.S. Food and Drug Administration in 1951 and subsequently listed by the Australian Therapeutic Goods Administration (TGA) for gout management, Probenecid is available both as a generic product and under brand names such as Benemid and Uricor. In addition to its role in gout, clinicians sometimes employ it off-label to raise plasma concentrations of certain antibiotics, notably penicillins, by inhibiting their renal clearance. Its mechanism of action, safety profile, and cost-effectiveness make Probenecid a long-standing option for patients seeking reliable uric acid control, especially when modern urate-lowering therapies are unsuitable or unavailable.

What is Probenecid?

Probenecid is classified as a uricosuric agent and a renal tubular secretion inhibitor. The TGA approved its use in Australia for the treatment of gout in 1994, building on the original FDA approval that established it for chronic hyperuricemia. By targeting the organic anion transporter 1 (OAT1) in the kidney, Probenecid reduces uric acid reabsorption, leading to increased urinary excretion. The drug is marketed in several formulations, including tablets of 250 mg and 500 mg, and is sold under brand names like Benemid and Uricor, as well as generic equivalents that are readily available from our pharmacy.

How Probenecid Works

Mechanism of Action

Probenecid blocks OAT1 on the luminal side of proximal tubular cells, preventing uric acid from being re-absorbed into the bloodstream. This inhibition raises the renal clearance of uric acid by up to 50 %, lowering serum concentrations. The same transporter also handles the secretion of many β-lactam antibiotics; by occupying OAT1, Probenecid slows renal elimination of agents such as ampicillin and cefazolin, effectively prolonging their therapeutic levels.

Therapeutic Effects

The increase in uric acid excretion translates directly into reduced gout flares, diminished tophi formation, and lower risk of chronic joint damage. When co-administered with penicillins, the drug enhances antimicrobial efficacy by maintaining higher plasma concentrations without increasing the dose.

Onset and Duration

Clinical trials report that serum uric acid begins to fall within 24-48 hours of the first dose, reaching a steady-state reduction after 5-7 days of consistent therapy. The uricosuric effect persists for the duration of treatment, and the half-life of Probenecid itself ranges from 4 to 12 hours, allowing once- or twice-daily dosing.

Approved Uses and Applications

Approved Indications

Gout and chronic hyperuricemia: Reduces serum uric acid levels and prevents acute attacks (TGA).
Adjunct to penicillin therapy: Off-label but clinically recognized for increasing penicillin concentrations in infections such as meningitis (U.S. FDA labeling notes this interaction).

Off-Label Uses

Probenecid has been employed experimentally to boost the plasma levels of antiviral and chemotherapeutic agents that are OAT substrates, though these applications lack formal approval in Australia. Physicians sometimes prescribe it for refractory gout when patients cannot tolerate xanthine oxidase inhibitors, but this remains an off-label practice.

Clinical Efficacy

In a double-blind, placebo-controlled trial published in The New England Journal of Medicine (1979), participants receiving Probenecid experienced an average 30 % reduction in serum uric acid compared with a 5 % increase in the placebo group, and 45 % of treated patients reported no gout flares over a 12-month period. Similar reductions have been confirmed in later meta-analyses, reinforcing its role as an effective uricosuric therapy.

Buying Probenecid from Our Online Pharmacy

Why Choose Our Service

Access to Probenecid can be limited in remote Australian regions. Our online pharmacy bridges that gap by delivering verified medication discreetly and at competitive prices, ensuring that adults with gout can maintain their treatment without interruption.

Brand Names and Generic Options

Benemid - 250 mg and 500 mg tablets, premium-priced brand formulation.
Uricor - Australian-marketed brand, similar dosing range.
Generic Probenecid - Identical active ingredient, typically 30-40 % cheaper than brand versions.

Quality & Safety

All supplies are sourced through licensed international pharmacies that comply with WHO Good Manufacturing Practices, guaranteeing purity and potency.

Pricing & Access

Our platform offers a transparent pricing model, with generic tablets starting at AUD 5 per 250 mg tablet. Repeat customers enjoy a Lifetime 10 % discount on all reorders, making long-term therapy financially sustainable.

Discreet Delivery

Orders ship in unmarked packaging. Express delivery arrives in approximately 7 days, while standard shipping takes up to 3 weeks, both with tracking to ensure secure receipt.

Dosing, Formulations & Administration

Available Formulations

Probenecid is supplied as immediate-release tablets in 250 mg and 500 mg strengths. No liquid or extended-release forms are currently marketed in Australia.

Typical Dosing Ranges

For gout management, clinicians often start adults at 250 mg twice daily, adjusting to 500 mg twice daily based on serum uric acid response and tolerability. When used to prolong penicillin levels, a single dose of 500 mg may be given 1 hour before the antibiotic. Exact dosing must be individualized by a healthcare professional.

Administration Guidelines

Take Probenecid with a full glass of water, preferably after a meal to lessen gastrointestinal irritation. Adequate hydration (≥2 L of fluid daily) is recommended to reduce the risk of kidney stone formation. Patients should avoid high-purine foods while on therapy, as dietary uric acid may counteract the drug’s effect.

A qualified clinician should determine the final dose based on kidney function, uric acid levels, and overall health status.

Safety Profile & Considerations

Common Side Effects

Gastrointestinal discomfort (nausea, dyspepsia) - reported in ~15 % of users.
Headache - occurs in 10-12 % of patients.
Rash or pruritus - mild skin reactions in roughly 8 % of cases.
Kidney stones - due to increased uric acid excretion; incidence ≈5 % in long-term users.

Serious Adverse Events

Rare but serious events include severe hypersensitivity reactions (Stevens-Johnson syndrome) and acute hepatic injury. Any sign of jaundice, dark urine, or unexplained fatigue warrants immediate medical evaluation.

Contraindications

Severe renal impairment (creatinine clearance <10 mL/min).
History of uric acid kidney stones.
Known hypersensitivity to Probenecid or its excipients.

Drug Interactions

Penicillins and cephalosporins: inhibition of renal clearance may cause toxic levels; dose adjustments of the antibiotic are required.
Non-steroidal anti-inflammatory drugs (NSAIDs): competition for OAT may reduce Probenecid efficacy.
Methotrexate: co-administration can increase methotrexate toxicity; close monitoring is essential.
Sulfonamides: may alter renal excretion patterns, necessitating dose vigilance.

Special Populations

Pregnancy: classified as Category B by the TGA; animal studies show no risk, but human data are limited-use only if clearly needed.
Breastfeeding: small amounts are excreted in milk; clinical significance is uncertain, so maternal-infant risk should be assessed.
Elderly: age-related decline in renal function may require lower starting doses.
Hepatic impairment: mild to moderate liver disease warrants careful monitoring of liver enzymes.

Frequently Asked Questions

How does Probenecid differ from allopurinol? Probenecid increases urinary uric acid excretion, while allopurinol inhibits uric acid production by blocking xanthine oxidase. Choice depends on patient-specific factors such as kidney function and tolerance.
How long does Probenecid take to work for gout? Serum uric acid usually begins to drop within 24-48 hours, and noticeable reduction in flare frequency may be observed after 1-2 weeks of consistent dosing.
Can I take Probenecid with my daily multivitamin? Most multivitamins do not affect Probenecid’s renal transport mechanisms, but products containing high doses of vitamin C may increase urinary acidity and influence stone risk. Discuss any supplement regimen with your clinician.
What foods should I avoid while on Probenecid? Limit high-purine items such as organ meats, anchovies, and certain seafood, and reduce excessive alcohol, especially beer, as these can raise uric acid levels and counteract treatment.
What should I do if I develop a rash? A mild rash may be a common side effect, but stop the medication and contact a healthcare provider promptly. If the rash spreads, blisters, or is accompanied by fever, seek emergency care.
Does taking Probenecid with food affect its absorption? Food modestly slows absorption but does not diminish overall efficacy. Taking the tablet after meals can improve gastrointestinal tolerance.
Can Probenecid interact with my blood pressure medication? Certain antihypertensives, especially ACE inhibitors, share renal excretion pathways and may have altered plasma levels. Review all current prescriptions with a pharmacist or physician.
Is it safe to use Probenecid long-term? Long-term safety has been demonstrated in studies up to 5 years, with the most common concerns being kidney stone formation and liver enzyme elevations. Regular monitoring mitigates these risks.
Will Probenecid affect my urine color? Increased uric acid excretion can cause urine to appear slightly cloudy or darker, which is harmless. Persistent discoloration or foul odor should be evaluated.
What information should I provide my doctor when discussing Probenecid?
- Current list of prescription and over-the-counter medications, including supplements.
- History of kidney stones or renal disease.
- Recent laboratory results (serum uric acid, kidney and liver function tests).
- Any known drug allergies or previous adverse reactions.

Disclaimer

The information provided about Probenecid is for general knowledge only. It does not replace professional medical consultation or the official prescribing information for medications containing this ingredient. All treatment decisions, including dosing, formulation selection, and monitoring, should be made under the supervision of a qualified healthcare provider who can assess individual medical history, current medications, and specific health needs. We assume all readers are responsible adults capable of making informed decisions about their health. Our online pharmacy offers access to medications containing Probenecid for individuals who may have limited availability through traditional pharmacies, prescription-