ヘパリンナトリウム
Heparin Sodium
Unfractionated Heparin (UFH)
別名: Hep-Lock · Hep-Loc U/P · Hepflush-10 · Unfractionated Heparin · UHF · heparinum natricum · sodium heparin · soluble heparin
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Thromboprophylaxis (extra-label)
認証済み獣医師の確認が必要
- q6h
NA
必ず考慮する臨床コンテキスト (2)
- Heparin is an anionic, heterogeneous sulfated glycosaminoglycan molecule with an average molecular weight of 12,000 daltons that is found naturally in mast cells. It is available commercially as the sodium salt and is obtained from either porcine intestinal mucosa or bovine lung tissue (sodium salt only). Heparin sodium occurs as a white, amorphous, hygroscopic powder having a faint odor. It is soluble in water and practically insoluble in alcohol; the commercial injections have a pH of 5 to 7.5. Heparin potency is expressed in terms of USP heparin units, and values are obtained by comparing against a standard reference from the USP. The USP requires that potencies be not less than 180 units/mg on a dried basis for heparin derived from lung tissue, and 140 units/mg when derived from all other tissue sources.
- Heparin solutions should be stored at room temperature (15°C-30°C [59°F-86°F]) and not frozen. Avoid excessive exposure to heat.
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
ヘパリンナトリウムは、獣医療において主に血栓塞栓症の管理や、議論の余地はあるものの播種性血管内凝固症候群（DIC）の治療に使用される注射用抗凝固薬です。
主な臨床応用：
- 血栓予防：高リスク患者における大血管血栓塞栓症の発生率を低下させる強力なエビデンスがあります。
- DICの管理：歴史的にDICに使用されてきましたが、現在のコンセンサスでは、炎症プロセスを併発しているDIC患者への使用は推奨されていません。
- 馬の医療：蹄葉炎の予防、DIC、および術後の腸管癒着を予防するための腹腔内洗浄に使用されます。
臨床のポイント：未分画ヘパリン（UFH）は、低分子量ヘパリン（LMWH）と比較して薬物動態プロファイルが非常に不安定です。治療効果を確保し、致命的な出血を避けるために、aPTTまたは抗Xa活性の厳密なモニタリングが必要です。
作用機序
Heparin acts as an indirect anticoagulant by binding to and potentiating the activity of Antithrombin III (ATIII).
- Low Concentrations: The Heparin-ATIII complex rapidly inactivates Factor Xa, preventing the conversion of prothrombin to thrombin.
- High Concentrations: The complex inactivates Thrombin (Factor IIa), blocking the conversion of fibrinogen to fibrin, and also inactivates factors IX, XI, and XII.
- Fibrin Stabilization: By inhibiting the activation of Factor XIII, heparin prevents the formation of stable fibrin clots.
Note: Heparin does not lyse existing clots (it is not a thrombolytic); rather, it prevents the expansion of existing thrombi and the formation of new ones. It also increases the release of lipoprotein lipase, boosting the clearance of circulating lipids.
安全性・警告
禁忌
- Known hypersensitivity to heparin
- Severe thrombocytopenia
- Uncontrollable bleeding (not caused by DIC)
- Intramuscular (IM) administration (causes hematomas)
- Actively bleeding DIC patients with severe factor depletion
有害事象
- Hemorrhage (most common)
- Thrombocytopenia
- Hypersensitivity reactions (derived from bovine/porcine tissue)
- Anemia in horses (due to erythrocyte agglutination)
- Injection site pain and hematoma (especially if given IM)
- Vasospastic reactions
- Osteoporosis (with long-term use)
- Rebound hyperlipidemia
- Hyperkalemia
- Alopecia
注意事項
Use with extreme caution in patients with dysfunctional interactions between inflammatory and hemostatic systems (e.g., DIC with concurrent inflammation). Do not administer IM due to the risk of severe hematoma formation. Deep SC dosing may cause pain and irritation. Dogs with renal insufficiency may have lower plasma levels and faster elimination rates, requiring dosage adjustments. Safe use in pregnancy is not firmly established (FDA Category C).
医薬品相互作用
May increase the risk for hemorrhage
May increase the risk for hemorrhage
May increase the risk for hemorrhage
May increase the risk for hemorrhage
May partially counteract heparin's anticoagulant effects
May partially counteract heparin's anticoagulant effects
May partially counteract heparin's anticoagulant effects
May partially counteract heparin's anticoagulant effects
May partially counteract heparin's anticoagulant effects
監視
- Activated partial thromboplastin time (aPTT) - most often recommended
- Whole blood clotting time (WBCT)
- Partial thromboplastin time (PTT)
- Activated clotting time (ACT)
- Thromboelastography (TEG)
- Platelet counts
- Packed cell volume (PCV) / Hematocrit
- Occult blood in stool and urine
- Clinical signs of bleeding or efficacy
薬物動態
吸収
Not absorbed orally; must be given parenterally. Anticoagulant activity begins immediately after direct IV bolus, but may take up to 1 hour after deep SC injection. Bioavailability after SC injection in healthy dogs is about 50%.
分布
Extensively protein bound, primarily to fibrinogen, low-density lipoproteins, and globulins. Does not appreciably cross the placenta or enter milk.
代謝
Metabolic fate is not completely understood. Partially metabolized by the liver and inactivated by the reticuloendothelial system.
消失
Eliminated via hepatic metabolism and the reticuloendothelial system. Dogs with renal insufficiency may have faster elimination rates.
過剰投与
Overdosage of heparin is directly associated with severe bleeding.
Clinical signs preceding frank hemorrhage include:
- Hematuria
- Tarry stools (melena)
- Petechiae and ecchymoses (bruising)
Reversal: Protamine sulfate can be administered to reverse heparin's anticoagulant effects. It binds to heparin to form a stable, inactive complex.
製品
製剤
- Injection solutions (1,000 to 40,000 Units/mL)
- Unit-Dose injections
- Heparin Sodium Lock Flush (10 to 100 Units/mL)
- Heparin Sodium in 0.9% or 0.45% Sodium Chloride
ヒト用医薬品
- Heparin Sodium Injection: 1000, 2000, 2500, 5000, 10,000, 20,000, & 40,000 Units/mL
- Heparin Unit-Dose Sodium Injection: 1000 to 20,000 Units/dose
- Heparin Sodium and 0.9% or 0.45% Sodium Chloride Injection
- Heparin Sodium Lock Flush (IV use) Injection: 1, 10, and 100 Units/mL
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 solutions at room temperature (15-30°C). Do not freeze. Avoid excessive exposure to heat.
飼主向け情報
ヘパリンは、生命を脅かす血栓の治療または予防に使用される強力な血液サラサラの薬（抗凝固薬）です。
- 入院治療：ヘパリンの使用には厳密なモニタリング（凝固時間を確認するための頻繁な血液検査）が必要であり、治療対象となる病気も重篤であるため、この薬はほぼ例外なく動物病院の入院環境で専門家によって使用されます。
- 出血のリスク：最も重大なリスクは出血です。もしペットがヘパリンに似た薬を処方されて退院した場合は、あざ、歯茎からの出血、尿や便への血液の混入、または極度の無気力などの兆候がないか注意深く観察し、異常があればすぐに獣医師に連絡してください。
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。