A-Z Drug Facts > Probenecid/Colchicine

Probenecid / Colchicine

Pronunciation: (pro-BEN-uh-sid/KOHL-chih-seen)
Class: Agents for gout

Trade Names:
Probenecid and Colchicine
- Tablets 500 mg probenecid and 0.5 mg colchicine

Pharmacology

Probenecid

Inhibits tubular reabsorption of urate, thus increasing urinary excretion of uric acid.

Colchicine

Inhibits inflammation and reduces pain and swelling associated with gouty arthritis.

Indications and Usage

Treatment of chronic gouty arthritis when complicated by frequent, recurrent, acute attacks of gout.

Contraindications

Hypersensitivity to any component of product; children younger than 2 yr of age; known blood dyscrasias; uric acid kidney stones; current acute gouty attack.

Dosage and Administration

Adults

PO 1 tablet/day for 7 days, then 1 tablet twice daily thereafter. If necessary, the daily dosage may be increased by 1 tablet at 4-wk intervals as tolerated (usually not more than 4 tablets/day).

General Advice

Administer without regard to meals. Administer with food if GI upset occurs.

Storage/Stability

Store tablets at controlled room temperature (59° to 86°F).

Drug Interactions

Acetaminophen, indomethacin, ketoprofen, lorazepam, meclofenamate, naproxen, rifampin

Plasma levels of these agents may be increased.

Beta-lactam antibiotics, penicillins

Psychic disturbances may occur.

Induction anesthesia (eg, thiopental)

Less anesthetic may be required.

Methotrexate

Probenecid increases plasma levels; methotrexate dose may need to be reduced.

Pyrazinamide, salicylates

Uricosuric action of probenecid may be antagonized.

Sulfonamides

Total sulfonamide (drug plus metabolite) levels may be increased.

Sulfonylureas

Risk of hypoglycemia may be increased.

Laboratory Test Interactions

Falsely high reading for theophylline may occur when measured by the Schack and Waxler technique.

Adverse Reactions

CNS

Probenecid

Headache; dizziness.

Colchicine

Peripheral neuritis.

Dermatologic

Probenecid

Urticaria; pruritus; dermatitis; alopecia; flushing.

Colchicine

Urticaria; purpura; alopecia; dermatitis.

GI

Probenecid

Vomiting; nausea; anorexia; sore gums.

Colchicine

Nausea; vomiting; abdominal pain; diarrhea.

Genitourinary

Probenecid

Nephrotic syndrome; uric acid stones with or without hematuria; renal colic; costovertebral pain; urinary frequency.

Hematologic

Probenecid

Aplastic anemia; leukopenia; hemolytic anemia.

Colchicine

Aplastic anemia; agranulocytosis.

Hepatic

Probenecid

Hepatic necrosis.

Metabolic

Probenecid

Precipitation of acute gouty arthritis.

Miscellaneous

Probenecid

Anaphylaxis; fever.

Colchicine

Muscular weakness.

Precautions

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy not established; contraindicated in children younger than 2 yr of age.

Renal Function

May not be effective in patients with chronic renal function impairment (30 mL/min or less); dose may need to be increased.

Alkalinization of urine

May be needed to prevent hematuria, renal colic, costovertebral pain, formation of uric acid stones.

Exacerbation of gout

May occur.

Peptic ulcer

Use with caution in patients with history of peptic ulcer disease.

Overdosage

Symptoms

Diarrhea, generalized vascular damage, renal damage, hematuria, oliguria.

Patient Information

• Advise patient to take tablets as prescribed by health care provider.
• Advise patient to take without regard to meals but to take with food if GI upset occurs.
• Inform patient that dose will be slowly increased until max benefit is obtained.
• Advise patient to maintain adequate fluid intake (at least eight 8 oz glasses of water/day) and to carefully follow any instructions regarding alkalinizing the urine that were provided by health care provider.
• Caution patient to not increase the dose of this medication if gout symptoms should recur. Instruct patient to discuss other treatments for acute gout while continuing this medication.
• Caution patient to avoid concurrent use of aspirin or aspirin-containing products. Advise patient to use acetaminophen for management of mild to moderate pain.
• Advise patient to stop taking the drug and notify health care provider if persistent diarrhea or other GI symptoms occur, or if a rash or other signs of an allergic reaction develop.

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