Diferencia entre revisiones de «Uricosuric Agent»

Revisión actual - 00:57 28 ene 2026

General

Indications: Chronic Gout (prevention), Hyperuricemia, Adjunct to antibiotic therapy (specific agents only)
Mechanism: Increases renal excretion of uric acid
Common Agents:

Probenecid

Secondary Agents (Off-label/Minor effect):

Emergency Medicine Clinical Pearls

Acute Gout Flares: Do NOT initiate uricosuric agents during an acute gout attack; mobilizing urate stores can worsen or prolong the flare.
Complications: The rapid increase in urinary uric acid can precipitate Nephrolithiasis (Uric Acid Stones). Patients must maintain high fluid intake (2-3L/day).
ASA Interaction: Salicylates (like Aspirin) antagonize the uricosuric action of these drugs.
Biphasic Effect: Sub-therapeutic doses may inhibit tubular secretion without inhibiting reabsorption, paradoxically increasing serum uric acid levels.

Pharmacology

Mechanism of Action

Acting primarily at the Proximal Convoluted Tubule of the kidney.
Inhibits URAT1 (Urate Transporter 1) and OAT4 (Organic Anion Transporter 4) on the apical membrane.
Blocks the active reabsorption of uric acid from the urine back into the blood, resulting in a net increase in uric acid excretion.

Pharmacokinetics

Absorption: generally well-absorbed orally.
Protein Binding: High (85-95%).
Metabolism: Hepatic.
Excretion: Renal/Biliary.

Adverse Reactions

Acute

Nausea and Vomiting (GI intolerance is common)
Rash / Hypersensitivity
Nephrolithiasis (Renal Colic) due to uricosuria
Paradoxical precipitation of acute Gout arthritis

Serious

Nephrotic Syndrome
Hepatic Necrosis (rare, associated with Benzbromarone)
Bone Marrow Suppression / Aplastic Anemia
Hemolytic Anemia (in patients with G6PD Deficiency)

Contraindications

Absolute

History of Uric Acid Kidney Stone
Hypersensitivity to the specific agent
Children < 2 years (specifically Probenecid)
High-grade renal insufficiency (CrCl < 30 mL/min) – drugs rely on renal flow to work effectively

Relative

Acute Gout Attack (wait until attack resolves before initiating)
Peptic Ulcer Disease (specifically Sulfinpyrazone)
Concomitant use with drugs dependent on renal excretion (see Interactions)

Drug Interactions

Note: This class (especially Probenecid) is notorious for inhibiting the renal excretion of other organic acids.
Increased Toxicity Risk:
- Methotrexate (can be fatal)
- Ketorolac and other NSAIDs
- Penicillin / Cephalosporins (often used therapeutically to boost levels, but can lead to toxicity if unplanned)
- Sulfonylureas (Risk of Hypoglycemia)
Decreased Efficacy:
- Salicylates (Aspirin) > 325mg/day block the uricosuric effect.

References

Authors:

Daniel Ostermayer

@@ Línea 1: / Línea 1: @@
-[[Has type::Page]]
+==General==
+*Indications: Chronic [[Gout]] (prevention), Hyperuricemia, Adjunct to antibiotic therapy (specific agents only)
+*Mechanism: Increases renal excretion of uric acid
+*Common Agents:
+{{#ask:[[Is DrugClass::Uricosuric Agent]] |format=ul }}
+*Secondary Agents (Off-label/Minor effect):
+**[[Losartan]]
+**[[Fenofibrate]]
+**[[Atorvastatin]]
+==Emergency Medicine Clinical Pearls==
+*'''Acute Gout Flares:''' Do NOT initiate uricosuric agents during an acute gout attack; mobilizing urate stores can worsen or prolong the flare.
+*'''Complications:''' The rapid increase in urinary uric acid can precipitate [[Nephrolithiasis]] (Uric Acid Stones). Patients must maintain high fluid intake (2-3L/day).
+*'''ASA Interaction:''' Salicylates (like [[Aspirin]]) antagonize the uricosuric action of these drugs.
+*'''Biphasic Effect:''' Sub-therapeutic doses may inhibit tubular secretion ''without'' inhibiting reabsorption, paradoxically increasing serum uric acid levels.
+==Pharmacology==
+===Mechanism of Action===
+*Acting primarily at the Proximal Convoluted Tubule  of the kidney.
+*Inhibits '''URAT1''' (Urate Transporter 1) and '''OAT4''' (Organic Anion Transporter 4) on the apical membrane.
+*Blocks the active reabsorption of uric acid from the urine back into the blood, resulting in a net increase in uric acid excretion.
+===Pharmacokinetics===
+*'''Absorption:''' generally well-absorbed orally.
+*'''Protein Binding:''' High (85-95%).
+*'''Metabolism:''' Hepatic.
+*'''Excretion:''' Renal/Biliary.
+==Adverse Reactions==
+===Acute===
+*[[Nausea and Vomiting]] (GI intolerance is common)
+*[[Rash]] / Hypersensitivity
+*[[Nephrolithiasis]] (Renal Colic) due to uricosuria
+*Paradoxical precipitation of acute [[Gout]] arthritis
+===Serious===
+*[[Nephrotic Syndrome]]
+*Hepatic Necrosis (rare, associated with Benzbromarone)
+*Bone Marrow Suppression / Aplastic Anemia
+*Hemolytic [[Anemia]] (in patients with [[G6PD Deficiency]])
+==Contraindications==
+===Absolute===
+*History of Uric Acid [[Kidney Stone]]
+*Hypersensitivity to the specific agent
+*Children < 2 years (specifically [[Probenecid]])
+*High-grade renal insufficiency (CrCl < 30 mL/min) – drugs rely on renal flow to work effectively
+===Relative===
+*Acute [[Gout]] Attack (wait until attack resolves before initiating)
+*Peptic Ulcer Disease (specifically Sulfinpyrazone)
+*Concomitant use with drugs dependent on renal excretion (see Interactions)
+==Drug Interactions==
+*''Note: This class (especially Probenecid) is notorious for inhibiting the renal excretion of other organic acids.''
+*'''Increased Toxicity Risk:'''
+**[[Methotrexate]] (can be fatal)
+**[[Ketorolac]] and other NSAIDs
+**[[Penicillin]] / [[Cephalosporins]] (often used therapeutically to boost levels, but can lead to toxicity if unplanned)
+**Sulfonylureas (Risk of [[Hypoglycemia]])
+*'''Decreased Efficacy:'''
+**Salicylates (Aspirin) > 325mg/day block the uricosuric effect.
+==See Also==
+*[[Gout]]
+*[[Probenecid]]
+*[[Nephrolithiasis]]
+*[[Hyperuricemia]]
+*[[Allopurinol]] (Xanthine Oxidase Inhibitor - distinct class)
+==References==
+<references/>
+[[Category:Pharmacology]] [[Category:Rheumatology]] [[Category:Renal]]