ジクロルフェナミド
Dichlorphenamide
別名: Daranide · Antidrasi · Fenamide · Glaucol · Glauconide · Glaumid · Oralcon · Oratrol · Tensodilen · Diclofenamidum
VetSheet 獣医チームが監修更新日 2026年4月5日エビデンスに基づく獣医学リファレンス
監査済み v13 用量エビデンス
構造化された用量計算エビデンスAdjunctive glaucoma treatment (extra-label)
- q8-12h
NA
必ず考慮する臨床コンテキスト (2)
- ■ Give this medicine as directed by your veterinarian. If your animal vomits or acts sick after receiving the medicine on an empty stomach, try giving the next dose with food or a small treat. If vomiting continues, contact your veterinarian.
- Store tablets in well-closed containers and at room temperature (20°C-25°C [68°F-77° F]).
用量は獣医専門家向けの臨床参考資料です。必ず最新の医薬品情報および個別症例に基づいて確認してください。
概要
ジクロルフェナミドは全身性の炭酸脱水酵素阻害薬（CAI）であり、獣医眼科において緑内障の内科的治療に従来使用されてきました。
- 臨床のポイント: 代謝性アシドーシスや低カリウム血症などの重大な全身性副作用と、商業的な入手の困難さから、全身性CAIは現在、ドルゾラミドやブリンゾラミドなどの局所点眼薬に大きく取って代わられています。
- 現在処方される場合、通常は調剤薬局（コンパウンディング薬局）を通じて入手する必要があります。
- 軽度の抗けいれん作用および利尿作用を持っていますが、現代の獣医学においてこれらの適応で使用されることは稀です。
作用機序
Dichlorphenamide exerts its effects via noncompetitive, reversible inhibition of the enzyme carbonic anhydrase (CA).
- In the ciliary body: Inhibition of CA-II → decreased formation of bicarbonate (HCO3-) and hydrogen (H+) ions from carbon dioxide and water → reduced active transport of sodium into the posterior chamber → decreased aqueous humor production → lowered intraocular pressure (IOP).
- In the kidneys: Inhibits CA in the proximal convoluted tubule → increased renal tubular secretion of Na+, K+, and HCO3- → alkaline diuresis and potential metabolic acidosis.
- In the CNS: Exhibits mild anticonvulsant activity, likely secondary to localized metabolic acidosis or direct CA inhibition in the brain.
安全性・警告
禁忌
- Significant hepatic disease (may precipitate hepatic coma)
- Renal or adrenocortical insufficiency
- Hyponatremia
- Hypokalemia
- Hyperchloremic acidosis
- Electrolyte imbalance
- Severe pulmonary obstruction (unable to increase alveolar ventilation)
- Hypersensitivity to carbonic anhydrase inhibitors
- Chronic, noncongestive, angle-closure glaucoma (long-term use)
有害事象
- Panting
- GI disturbances (inappetence, vomiting, diarrhea)
- CNS effects (sedation, depression, excitement)
- Hematologic effects (bone marrow depression)
- Renal effects (crystalluria, dysuria, renal colic, polyuria)
- Metabolic acidosis
- Hypokalemia
- Hyperglycemia
- Hyponatremia
- Hyperuricemia
- Hepatic insufficiency
- Dermatologic effects (rash)
- Hypersensitivity reactions
注意事項
Warning: Long-term use is contraindicated in patients with chronic, noncongestive, angle-closure glaucoma as it may mask the condition by lowering IOP while angle closure progresses.
- Use with extreme caution in patients with pre-existing electrolyte imbalances (especially hypokalemia or hyponatremia).
- May precipitate hepatic coma in patients with severe liver disease.
- Avoid in patients with severe pulmonary obstruction who cannot increase alveolar ventilation to compensate for metabolic acidosis.
- Pregnancy Category C: Teratogenic effects observed in animal studies; use only if benefits outweigh risks.
- Laboratory Interference: May cause false-positive results for urine protein using certain test methods (e.g., bromphenol blue, sulfosalicylic acid) due to urine alkalinization. May also decrease iodine uptake by the thyroid gland.
医薬品相互作用
Alkaline urine caused by dichlorphenamide may decrease excretion of tricyclic antidepressants.
Increased risk of dichlorphenamide accumulation and toxicity; increased risk for metabolic acidosis; dichlorphenamide increases salicylate excretion.
Dichlorphenamide may cause hypokalemia, leading to an increased risk for digoxin toxicity.
Rarely, carbonic anhydrase inhibitors interfere with the hypoglycemic effects of insulin.
Dichlorphenamide may negate the effects of methenamine in the urine due to alkalinization.
Concomitant use may exacerbate potassium depletion.
Increased urinary excretion, which may reduce phenobarbital levels.
Decreased primidone concentrations.
Alkaline urine caused by dichlorphenamide may decrease quinidine excretion.
監視
- Intraocular pressure (IOP) / tonometry
- Serum electrolytes (may need to supplement potassium)
- Baseline CBC with differential and periodic retests if using chronically
- Clinical signs of adverse effects (GI upset, panting, CNS changes)
薬物動態
吸収
Onset of action in small animals is approximately 30 minutes, with maximal effect occurring in 2-4 hours.
分布
Not well studied in domestic animals.
代謝
Not well studied in domestic animals.
消失
Duration of action in small animals is 8-12 hours.
過剰投与
Information regarding acute toxicity of dichlorphenamide is limited.
- Clinical Signs: Likely extensions of adverse effects, including severe electrolyte derangements (hypokalemia, hyponatremia), profound metabolic acidosis, CNS depression, and dehydration.
- Treatment:
- Monitor serum electrolytes, blood gases, volume status, and CNS status.
- Provide aggressive supportive care, including IV fluid therapy to correct dehydration and acid-base/electrolyte imbalances (e.g., potassium supplementation). Treat symptomatically.
製品
製剤
- Tablets (historically)
- Compounded oral formulations
動物用医薬品
- None commercially available (requires compounding)
ヒト用医薬品
- None commercially available (requires compounding)
規制ステータス
規制データなし: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Store tablets in well-closed containers and at room temperature. An expiration date of 5 years after the date of manufacture is assigned to the commercially available tablets (when available).
飼主向け情報
- 投与方法: 獣医師の指示通りに正確に投与してください。ペットに胃腸の不調（嘔吐や食欲不振）が見られる場合は、少量の食事やおやつと一緒に与えてみてください。
- 注意すべき症状: 以下の症状に気づいた場合は、すぐに獣医師に連絡してください：
- 異常な出血やあざ（骨髄抑制の兆候の可能性があります）。
- 筋肉の震え、脱力感、または重度の無気力（低カリウム血症の兆候）。
- 発疹や過度なパンティング（あえぎ呼吸）。
- フォローアップ: ペットの眼圧（緑内障）や血液検査（電解質や血球数）をモニターするために、定期的な診察が不可欠です。
注意: 市販の錠剤はほとんど入手できないため、この薬は通常オーダーメイド（調剤）されます。薬が切れる前に余裕を持って補充するようにしてください。
VetSheet医薬品リファレンスは獣医専門家の臨床意思決定支援を目的としており、専門的判断または製造業者の最新医薬品情報の代替にはなりません。