アセトヒドロキサム酸
**アセトヒドロキサム酸 (AHA)** は、主に犬の**難治性ストルバイト尿石症**（膀胱結石）および**ウレアーゼ産生菌**による慢性尿路感染症の補助治療として使用される特殊な薬剤です。 * **臨床のポイント**: 副作用が多いため、通常は標準的な抗生物質や食事療法が効かない難治性のケースにのみ使用されます。 * **警告**: 猫には重篤な毒性があるため絶対禁忌です。
作用機序: AHA acts as a potent, reversible inhibitor of the bacterial enzyme **urease**. * **Urease** normally hydrolyzes urea → ammonia + carbon dioxide. * By inhibiting **urease**, AHA → decreases urinary ammonia, bicarbonate, and carbonate concentrations → prevents the alkalinization of urine (keeps pH lower). * This acidic environment increases the solubility of struvite (magnesium ammonium phosphate) and carbonate-apatite crystals, and enhances the efficacy of concurrent antimicrobial therapy (e.g., carbenicillin, gentamicin, clindamycin, trimethoprim-sulfa, or chloramphenicol).
動物種別の用量
- Adjunctive therapy of persistent struvite uroliths and persistent urease-producing bacteria after treating with antibiotics and calculolytic diets · 12.5 mg/kg twice daily PO · PO · twice daily
用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。
投与経路
禁忌
- Cats (highly toxic)
- Patients with poor renal function (e.g., serum creatinine >2.5 mg/dL)
- Pregnancy (FDA Category X - severe teratogenic effects)
有害事象
- Anorexia
- Vomiting
- Mouth and esophageal ulcers
- Hemolytic anemia
- Hyperbilirubinemia
- Bilirubinuria
- CNS disturbances (anxiety, depression, tremulousness)
- Reticulocytosis
- Bone marrow depression
- Phlebitis
- Skin rashes and alopecia
薬物相互作用
- Iron salts · AHA may chelate iron salts in the gut if given concomitantly, reducing absorption.
- Methenamine · AHA may have a synergistic effect with methenamine in inhibiting urine pH increases caused by urease-producing Proteus spp., and may potentiate antibacterial effects.
- Alcohol · In humans, concurrent use of AHA with alcohol has resulted in skin rashes.
モニタリング
- CBC (Complete Blood Count)
- Renal function (including urinalysis)
- Hepatic function (specifically bilirubin levels)
過量投与
Acute overdoses can lead to severe hematologic and neurologic signs. * **Clinical Signs**: Anorexia, tremors, lethargy, vomiting, and anxiety. * **Hematologic Effects**: Increased reticulocyte counts and severe **hemolytic reactions**. Mild overdoses over several weeks can also result in hemolysis, particularly in patients with reduced renal function. * **Treatment**: Intensive hematologic monitoring with adjunctive supportive therapy, including possible blood transfusions.
VetSheet の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。