ミネラルオイル / 白色ワセリン
ミネラルオイルは、原油から抽出された透明で無色無臭の複雑な炭化水素の混合物です。獣医学においては、古典的な**潤滑性下剤**として、特に大型動物（馬など）の大結腸便秘や砂疝の治療に広く使用されています。 小動物では、主に猫の毛球症の管理や予防のために、風味付きのワセリンゲルの形で使用されます。さらに、特定の脂溶性毒素（メタアルデヒド、灯油など）の胃腸からの吸収を遅らせるために、胃チューブを介して投与されることもあります。 > **臨床のポイント：** 医療目的では、軽質ミネラルオイルよりも重質ミネラルオイルが推奨されます。これは、経口投与後に腸から吸収されたり誤嚥されたりするリスクが低いためです。
作用機序: Mineral oil and petrolatum act purely mechanically within the gastrointestinal tract: * **Lubrication:** Coats the intestinal mucosa and the fecal mass, reducing friction. * **Moisture Retention:** Creates a hydrophobic barrier that prevents the reabsorption of water from the GI tract → increases fecal bulk and softens the stool. * **Transit Time:** The increased bulk and lubrication stimulate peristalsis → decreases intestinal transit time. * **Toxin Sequestration:** Acts as an indigestible lipid sink in the gut lumen, trapping lipid-soluble toxins and preventing their systemic absorption.
動物種別の用量
- Laxative · 100-500 mL · Stomach tube
- Laxative · 100-500 mL · Stomach tube
- Laxative · 2-10 mL · PO · Because of the risk for aspiration, liquid mineral oil is rarely recommended for PO administration today.
- Laxative · 2-6 mL · PO
- Laxative · 5 mL · PO · q24h · Give per day with food
- Laxative · 1-4 liters · Stomach tube
- Laxative (Adults) · 0.5-2 liters · Stomach tube
- Laxative (Calves) · 60-120 mL · Stomach tube
- Adjunctive treatment of metaldehyde poisoning · 8 mL/kg · Stomach tube · May be used with a saline cathartic
- Adjunctive treatment of nitrate poisoning · 1 liter per 400 kg body weight · Stomach tube
投与経路
禁忌
- Patients with an increased risk of vomiting or regurgitation
- Dysphagia or swallowing difficulties
- Esophageal or gastric retention
- Hiatal hernia
- Debilitated or pregnant patients (based on human guidelines)
- Human pediatric patients under 6 years old
有害事象
- Lipid pneumonitis (severe, if aspirated)
- Granulomatous reactions in liver, spleen, and mesenteric lymph nodes (if absorbed)
- Anal oil leakage
- Decreased absorption of fat-soluble vitamins (A, D, E, K) with chronic use
薬物相互作用
- Docusate (DSS) · Theoretically enhances the absorption of mineral oil, which could lead to systemic granulomatous reactions. Avoid concurrent use, though clinical significance in large animals appears low.
- Vitamins A, D, E, K · Chronic administration of mineral oil may decrease the absorption of fat-soluble vitamins. Administer between meals to minimize this effect.
モニタリング
- Clinical efficacy (fecal output, resolution of impaction)
- Signs of aspiration (coughing, tachypnea, dyspnea)
- Auscultation and thoracic radiographs if aspiration is suspected
過量投与
Overdose effects are generally self-limiting (e.g., diarrhea, anal leakage). The primary life-threatening risk is **aspiration**, which can lead to severe lipid pneumonitis. Chronic overdosage may cause fat-soluble vitamin (A, D, E, K) deficiency.
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。