エピネフリン
Epinephrine
Levo-epinephrine
別名: EpiPen · Twinject · Adrenaline · Epinephrine HCl · Epinephrine bitartrate · Levo-epinephrine · Epinephrinum · L-epinephrine
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
確認済み・計算対象外のエビデンス確認済み・計算対象外のエビデンス (2)
エビデンス表示のみ（自動計算対象外）
Most species/CPR, cardiac arrest
TABLE 127.5. Agent: Epinephrine (1 : 1000). Dosage: 0.5–1 mg/kg IV, IO, IT232. Species/Comments: Most species/CPR, cardiac arrest.
エビデンス表示のみ（自動計算対象外）
Snapping turtles/reduction in time to spontaneous respiration after isoflurane anesthesia
TABLE 127.5. Agent: Epinephrine (1 : 1000). Dosage: 0.1 mg/kg IM106. Species/Comments: Snapping turtles/reduction in time to spontaneous respiration after isoflurane anesthesia.
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
エピネフリン（一般にアドレナリンとして知られる）は、副腎髄質で産生される強力な内因性カテコールアミンです。交感神経系の主要な「闘争か逃走か」のホルモンです。
獣医学においては、主に以下の目的で使用される極めて重要な救命救急薬です：
- 心肺脳蘇生法 (CPCR): 心停止（心静止）時の自己心拍再開を促すため。
- 重度のアナフィラキシー: 気管支拡張と血管収縮を誘発し、生命を脅かすアレルギー反応を急速に回復させるため。
- 局所麻酔の補助: 局所麻酔薬（リドカインなど）に添加し、局所の血管収縮を引き起こすことで、全身への吸収を遅らせ、麻酔効果を延長し、部位の出血を減少させるため。
臨床上のポイント: エピネフリンは非常に強力であり、治療域が非常に狭いです。正しい濃度が使用されていることを確認するために細心の注意を払う必要があります。1:1,000 (1 mg/mL) の濃度と 1:10,000 (0.1 mg/mL) の濃度を絶対に混同しないでください。
作用機序
Epinephrine is a direct-acting, non-selective adrenergic agonist that stimulates both alpha (α) and beta (β) receptors via G-protein coupled pathways (activating adenylyl cyclase → ↑ cAMP).
- α1-receptors: → Induces profound smooth muscle contraction and vasoconstriction, increasing systemic vascular resistance and blood pressure.
- β1-receptors: → Directly stimulates the heart, increasing both chronotropy (heart rate) and inotropy (contractility), which increases cardiac output and myocardial oxygen demand.
- β2-receptors: → Relaxes smooth muscle, leading to profound bronchodilation (relieving bronchospasm in anaphylaxis), vasodilation in skeletal muscle, and increased glycogenolysis (raising blood sugar).
- Histamine Antagonism: Physiologically antagonizes the effects of histamine released during anaphylaxis.
Hemodynamic effects depend on the route and rate of administration: Rapid IV injection causes direct cardiac stimulation and increased systolic BP. Slow IV infusion produces a modest rise in systolic pressure, a decrease in diastolic pressure, and decreased total peripheral resistance due to dominant β2 effects.
安全性・警告
禁忌
- Narrow-angle glaucoma
- Hypersensitivity to epinephrine
- Shock due to non-anaphylactoid causes
- During general anesthesia with halogenated hydrocarbons or cyclopropane
- During labor (may delay the second stage)
- Cardiac dilatation or coronary insufficiency
- Conditions where vasopressors are contraindicated (e.g., thyrotoxicosis, diabetes, hypertension, toxemia of pregnancy)
- Injection with local anesthetics into small appendages (toes, ears, etc.) due to risk of necrosis
有害事象
- Anxiety and fear
- Tremors and excitability
- Vomiting
- Hypertension (especially with overdosage)
- Cardiac arrhythmias (especially with pre-existing heart disease)
- Hyperuricemia
- Lactic acidosis (with prolonged use or overdose)
- Tissue necrosis and sloughing at the injection site (with repeated injections or injection into small appendages)
注意事項
Hypovolemia: Epinephrine is not a substitute for adequate fluid volume replacement therapy. Cardiac Rhythms: Use with extreme caution in patients with a prefibrillatory cardiac rhythm due to excitatory effects on the heart. While useful in asystole, it can cause ventricular fibrillation; use cautiously in cases of existing ventricular fibrillation. Tissue Necrosis: Do not inject into small appendages (ears, toes, tails) as profound vasoconstriction can cause ischemic necrosis and sloughing. Concentration Errors: Always double-check the concentration (1:1,000 vs 1:10,000) before administration to avoid fatal overdoses.
医薬品相互作用
May negate the therapeutic effects of epinephrine.
Do NOT use epinephrine to treat cardiac effects caused by alpha-2 agonists; may worsen hemodynamics.
Increased risk of developing severe arrhythmias. Propranolol may be used to treat if they occur.
May potentiate the effects of epinephrine.
May potentiate hypertension and antagonize epinephrine's cardiac and bronchodilating effects.
Increased risk of arrhythmias if used concurrently.
May reverse the pressor effects of epinephrine.
May potentiate the effects of epinephrine.
Hypertension may result if used concurrently.
Should not be administered together as increased toxicity may result.
May reverse the pressor effects of epinephrine.
May potentiate the pressor effects of epinephrine.
May potentiate the effects of epinephrine.
Additive effects leading to potential toxicity
May potentiate the effects of adrenaline
May potentiate the effects of adrenaline
May block the beta effects of adrenaline, facilitating an increase in blood pressure
May negate or diminish the pressor effects of adrenaline
May negate or diminish the pressor effects of adrenaline
Sensitizes the myocardium, increasing the risk of arrhythmias
Sensitizes the myocardium, increasing the risk of arrhythmias
Sensitizes the myocardium to catecholamines, increasing the risk of severe ventricular arrhythmias.
Antagonizes the beta-adrenergic effects of epinephrine, leaving unopposed alpha-adrenergic vasoconstriction which can lead to severe hypertension.
May potentiate the cardiovascular effects of epinephrine.
May reverse the pressor effects of epinephrine, potentially leading to vasodilation and hypotension (epinephrine reversal).
監視
- Cardiac rate and rhythm (ECG)
- Respiratory rate and auscultation (especially during anaphylaxis)
- Urine flow (if possible)
- Blood pressure
- Blood gases (if indicated and possible)
薬物動態
吸収
Well-absorbed following IM or SC administration. IM injections are slightly faster absorbed than SC; massaging the site expedites absorption. Rapidly metabolized in the GI tract and liver after oral administration (not effective PO). SC onset of action is 5-10 minutes. IV onset is immediate.
分布
Does not cross the blood-brain barrier. Crosses the placenta and is distributed into milk.
代謝
Actions are ended primarily by uptake and metabolism into sympathetic nerve endings. Metabolized in the liver and other tissues by monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT) to inactive metabolites.
消失
Excreted as inactive metabolites.
過剰投与
Clinical signs of overdosage or inadvertent IV administration of SC/IM doses include:
- Sharp rises in systolic, diastolic, and venous blood pressures
- Cardiac arrhythmias
- Pulmonary edema and dyspnea
- Vomiting, headache, and chest pain
- Cerebral hemorrhages (due to severe hypertension)
- Renal failure, metabolic acidosis, and cold skin
Treatment: Because epinephrine has a relatively short duration of effect, treatment is mainly supportive. If necessary, an alpha-adrenergic blocker (e.g., phentolamine) or a beta-adrenergic blocker (e.g., propranolol) can be used to treat severe hypertension and cardiac arrhythmias. Prolonged periods of hypotension may follow, requiring treatment with norepinephrine.
製品
製剤
- Injection solution (1:1,000 / 1 mg/mL)
- Injection solution (1:10,000 / 0.1 mg/mL)
- Auto-injectors (0.15 mg, 0.3 mg)
- Aerosol for inhalation
- Topical solution
- Solution for nebulization
- Ophthalmic preparations
動物用医薬品
- Epinephrine HCl for Injection 1 mg/mL (1:1,000) in 1 mL amps/syringes and 10 mL, 30 mL, 100 mL vials (Amtech, Am-Vet, Vedco, Vetus, AgriPharm, Durvet, Bimeda, etc.)
ヒト用医薬品
- Epinephrine HCl Solution for Injection: 1 mg/mL (1:1,000) in amps and vials (Adrenalin Chloride)
- Epinephrine HCl Solution for Injection auto-injectors: 1:1,000 (0.3 mg) (EpiPen, Twinject)
- Epinephrine HCl Solution for Injection auto-injectors: 1:2,000 (0.15 mg) (EpiPen Jr)
- Epinephrine HCl Solution for Injection: 1:10,000 (0.1 mg/mL) in syringes and vials
- Epinephrine bitartrate powder (aerosol) for inhalation
- Topical solutions
- Ophthalmic preparations
規制ステータス
プール期間: cattle meat 0 days · cattle milk 0 days
Commonly referred to as Adrenaline in EU regulatory documents.
プール期間: cattle meat 0 days · cattle milk 0 days
Commonly referred to as Adrenaline.
規制データなし: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Store in tight containers protected from light. Epinephrine will darken (oxidize) upon exposure to light and air. Do not use if the injection is pink, brown, or contains a precipitate. Rapidly destroyed by alkalies or oxidizing agents.
飼主向け情報
エピネフリンは、重度のアレルギー反応（アナフィラキシー）に使用される救命救急薬です。
- 緊急時のみ使用: ペットにプレフィルドシリンジ（エピペンなど）が処方されている場合は、獣医師の指示に従い、既知の重度のアレルギー反応に対してのみ使用してください。
- 直ちに受診を: エピネフリンを投与した後でも、直ちにペットを動物病院の救急外来に連れて行く必要があります。薬の効果はすぐに切れ、アレルギー反応が再発する可能性があります。
- 投与方法: 獣医師が実演した正しい注射技術（通常は筋肉内または皮下注射）を確実に理解してください。
- 保管: 光を避け、室温で保管してください。使用期限が切れている場合、液体がピンクや茶色に変色している場合、または浮遊物が見られる場合は、使用しないでください。
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。