probenecid

probenecid /pro·ben·e·cid/ (pro-ben´ĕ-sid) a uricosuric agent used in the treatment of gout; also used to increase serum concentration of certain antibiotics and other drugs.

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pro·ben·e·cid (pr-bn-sd)

n.

A uricosuric drug derived from benzoic acid and used chiefly in the treatment of gout.

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Probenecid

A drug that corrects hyperuricemia by increasing the urinary excretion of urate.

Mentioned in: Gout

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probenecid

[prōben′əsid]

a uricosuric and adjunct to antibiotics.

indications It is prescribed in the treatment of gout and as an adjunct to prolong the activity of penicillin or cephalosporins in some infections, such as gonorrhea.

contraindications Uric acid kidney stones, blood dyscrasias, or known hypersensitivity to this drug prohibits its use. It is not initiated during an acute attack of gout but is continued if an attack occurs during treatment. It is not given to children less than 2 years of age. Concomitant administration of salicylates decreases the effect of probenecid.

adverse effects Among the most serious adverse reactions are hemolytic anemia, GI disturbances, headache, urinary frequency, and minor allergic reactions. It is involved in many drug interactions, particularly with salicylate drugs.

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probenecid (prōben´isīd),

n brand names: Benemid, Probalan;
drug class: uricosuric;
action: inhibits tubular reabsorption of urates, with increased excretion of uric acids;
uses: hyperuricemia in gout, gouty arthritis, adjunct to cephalosporin or penicillin treatment by reducing excretion and maintaining high blood levels of medication.

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probenecid

used in the treatment of gout to promote excretion of uric acid; also used with certain antibiotics such as penicillin G and ampicillin to delay excretion and prolong their action.

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probenecid

Benuryl (CA)

Pharmacologic class: Sulfonamide-derived uricosuric

Therapeutic class: Antigout drug, tubular blocking agent

Pregnancy risk category B

Action

Promotes uric acid excretion from kidney by blocking tubular reabsorption; also inhibits tubular secretion of weak organic acids (most penicillins and cephalosporins, some beta-lactams)

Availability

Tablets: 0.5 g

⊘Indications and dosages

➣ Hyperuricemia caused by gout

Adults and children weighing more than 50 kg (110 lb): After acute gout attack subsides, 250 mg P.O. b.i.d. for 1 week, then 500 mg b.i.d.; may increase by 500 mg/day q 4 weeks (not to exceed 3 g/day)

➣ To prolong action or increase blood level of penicillins or cephalosporins

Adults: 500 mg P.O. q.i.d.

Children ages 2 to 14: Initially, 25 mg/kg or 0.7 g/m², then a maintenance dosage of 40 mg/kg/day or 1.2 g/m² in four divided doses

➣ Gonorrhea

Adults: 1 g P.O. as a single dose given with or immediately before prescribed ampicillin dose

Dosage adjustment

• Renal impairment

Off-label uses

• Hyperuricemia secondary to thiazide therapy

Contraindications

• Hypersensitivity to drug
• Acute gout attack
• Uric acid calculi
• Blood dyscrasias
• Concurrent salicylate use
• Concurrent penicillin use in patients with renal impairment
• Children younger than age 2

Precautions

Use cautiously in:
• peptic ulcer, renal impairment
• pregnant or breastfeeding patients.

Administration

☞ Don't give until acute gout attack subsides.
• Ensure high fluid intake and alkaline urine during therapy.

Route	Onset	Peak	Duration
P.O.	30 min	2-4 hr	8 hr

Adverse reactions

CNS: headache, dizziness

GI: nausea, vomiting, diarrhea, abdominal pain, anorexia

GU: urinary frequency, uric acid calculi, renal colic, nephrotic syndrome

Hematologic: anemia, hemolytic anemia, aplastic anemia

Hepatic: hepatitis, hepatic necrosis

Metabolic: gout exacerbation

Musculoskeletal: costovertebral pain

Skin: flushing, rash, pruritus

Other: sore gums, fever, hypersensitivity reactions including anaphylaxis

Interactions

Drug-drug. Acyclovir, allopurinol, barbiturates, cephalosporins, pantothenic acid, penicillins: increased blood levels of these drugs, enhanced uric acid-reducing effect of probenecid

Benzodiazepines: faster onset and prolonged effects of these drugs

Clofibrate: increased clofibrate blood level

Dapsone: accumulation of dapsone and its metabolites

Dyphylline: increased half-life and decreased clearance of dyphylline

Methotrexate, nonsteroidal anti-inflammatory drugs, rifampin, sulfonamides: increased blood levels, therapeutic effects, and toxicity of these drugs

Oral hypoglycemics: increased half-life and effects of these drugs

Penicillamine: increased pharmacologic effect of penicillamine

Salicylates: decreased probenecid or salicylate activity

Thiopental: extended anesthetic effect of thiopental

Zidovudine: increased risk of zidovudine toxicity

Drug-diagnostic tests. Urine glucose tests using copper reduction method (such as Clinitest): false-positive result

Patient monitoring

• Monitor kidney and liver function tests, CBC, and blood urea nitrogen level.
• Assess fluid intake and output to ensure good hydration and reduce urinary side effects.
• During first 6 to 12 months of therapy, monitor pattern and severity of acute gout attacks to assess need for additional anti-inflammatory drugs.

Patient teaching

• Advise patient to take with food or milk to minimize GI upset.
• Teach patient about causes of gout and proper use of drug. Stress that he must wait until acute attack subsides and then take drug regularly to prevent further attacks.
• Tell patient drug may exacerbate acute gout attacks for first 6 to 12 months, necessitating colchicine or other anti-inflammatory drug for 3 to 6 months.
• Instruct patient to drink 2 to 3 liters of fluids daily.
• Tell patient with gout to limit foods high in purine (such as anchovies, organ meats, and legumes).
• Instruct diabetic patient to test urine glucose level during therapy.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

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Patient discussion about probenecid.

Q. SVT and AF, Hearts that go fast to slow or any others probs with the beats of any kind and Ablation of hearts I have had Ablation done once and I am still having passing out spells and still on 50mg toprol 2 times a day till two days ago, now I am on 150 to 200 aday again. Its not the first time I have had to up meds. I had ablation down 4/22/05. I can breath better now but but it didnt take it away as you can tell. Now Dr Leonardie would like to do it again . This is the big ????! Will it or can it work 100% this time, or will it hit and miss some again???? MTT

A. Well I can understand the frustration of having to go through this procedure yet another time. There are no guarantees in medicine. You should follow your doctor's advice, as another proceudre might be more helpful than the last one. However you should keep in mind that nothing is for sure.