犬の慢性肝炎治療の最新概念 -4.肝不全合併症の対症療法


Other symptomatic therapy may include control of hepatic encephalopathy, coagulopathy, fluid and electrolyte imbalances, ascites, GI ulceration, and infection and/or endotoxemia.2, 3, 8

Hepatic encephalopathy can be exacerbated by hypokalemia, dehydration, alkalosis, GI bleeding, and constipation.

Treatment involves reducing ammonia production by decreasing dietary protein, controlling GI bleeding, and administering antibiotics effective against urease producing bacteria.

Antibiotics most commonly used include amoxicillin 22 mg/kg PO q 12 hrs, neomycin 22 mg/kg PO q 8–12 hrs, or metronidazole 7.5 mg/kg PO q 12 hrs.

Lowering the pH in the colon is also useful by inhibiting bacterial growth and converting ammonia to the nonabsorbable ammonium ion.

Lactulose given at 0.25–0.5 mls/kg PO q 8–12 hrs, decreases colonic pH and provides an osmotic laxative effect.

In cases of severe hepatic encephalopathy, lactulose can be given as an enema (diluted 1:3 with water).3, 8

Diluted povidone-iodine (Betadine, Purdue Frederick Co., Norwalk, CT) solution can also be used as an enema for treating severe hepatic encephalopathy if lactulose is not available.3, 15


Coagulopathies are common in animals with liver disease.

Possible mechanisms include decreased clotting factor synthesis, decreased vitamin K absorption in cholestatic disease, and disseminated intravascular coagulation.4

Parenteral vitamin K (0.5 to 2 mg/kg SQ q 12 h for 2 to 3 doses) may be helpful in correcting coagulopathies.3, 34

If vitamin K is ineffective, then blood products, such as whole blood or plasma, may be necessary to stabilize the coagulopathy before performing invasive procedures, such as a liver biopsy.


Ascites can be treated with diuretics, such as spironolactone and/or furosemide.

Furosemide is considered more potent but may cause hypokalemia and metabolic alkalosis, which can exacerbate hepatic encephalopathy.

Spironolactone is usually preferred because it is potassium sparing and directly inhibits aldosterone, which is thought to play a role in the production of ascites in dogs with liver disease.

The recommended dose of spironolactone is 1–2 mg/kg PO q 12 hrs. If this is ineffective, furosemide can be added at 1–2 mg/kg PO q 12–24 hrs.3, 8


GI ulcers are common in dogs with chronic liver disease.

Melena is not usually evident in physical examination, so its absence does not exclude the presence of GI ulcers.

GI ulcers should be suspected if there is any anorexia, vomiting, or anemia.

GI ulcers may be treated with a variety of medications, such as H2 blockers, sucralfate, or omeprazole.

Of the H2 blockers, famotidine (0.5–1 mg/kg PO q 12–24 hrs) is generally preferred because of the lack of cytochrome P450 enzyme inhibition.

Cimetidine (5–10 mg/kg PO q 6–8 hrs) and, to a lesser extent, ranitidine (2–3.5 mg/kg PO q 8–12 hrs) suppress the cytochrome P450 enzyme.

Omeprazole, a proton pump inhibitor, can be used at a dose of 0.7–2 mg/kg PO once daily.

The recommended dose of sucralfate is 0.5–1 gram per dog PO q 8–12 hrs.3, 7, 8, 10, 20


Antibiotics may be useful in some dogs with hepatitis, especially if the inflammation is suppurative, rather than mononuclear, in nature.7

Antibiotics that are most commonly used include amoxicillin, amoxicillin-clavulanic acid (Clavamox, Pfizer Inc, New York, NY) fluoroquinolones, and metronidazole (at a reduced dose of 7.5 mg/kg orally, twice per day).

Ideally, the choice of antibiotic should be based on culture and sensitivity results of bile or liver tissue.

Antibiotics that should generally be avoided in dogs with liver disease include sulfonamides, erythromycin, lincomycin, chloramphenicol, and tetracycline.8

Dogs with chronic liver disease can also be predisposed to endotoxemia because of decreased hepatic reticuloendothelial system function and GI ulceration.8

Bacteria from the GI tract may play a role in ascending cholangiohepatitis or hepatic encephalopathy.





最も一般的に使用される抗生物質は、アモキシシリン22 mg/kgを経口で12時間毎、ネオマイシン22mg/kg を経口で 8–12 時間毎、または メトロニダゾール7.5 mg/kgを経口で12時間毎の投与が含まれる。

細菌の増殖を抑制し、アンモニアを非吸収性のアンモニウムイオンに変換することによる結腸内 pH の低下もまた有用である。

ラクツロース 0.25–0.5 mls/kg の 8–12 時間毎の経口投与は結腸のpHを低下させ、浸透圧性緩下剤効果をもたらす。






経口ビタミンK投与(0.5 から 2 mg/kg SQを12時間毎に2から3用量)は血液凝固障害の補正に有効かも知れない。






スピロノラクトンの推奨用量では1–2 mg/kgを経口で12時間毎に投与する。

もしこれが効果がない場合は、フロセミド1–2 mg/kgを経口で12-24時間毎の投与を追加し得る。






H2ブロッカーのうち、ファモチジン(0.5-1 mg/kgを経口で 12–24時間毎に)は、シトクロムP450酵素を阻害しないので一般的に好まれる。

シメチジン(5-10 mg/kg を経口で 6–8 時間毎に)及び、それほどではないにせよラニチジン(2–3.5 mg/kg を経口で 8–12 時間毎に)はシトクロムP450酵素を阻害する。

プロトンポンプ阻害剤のオメプラゾールは0.7–2 mg/kg を一日一度経口投与で使用出来る。

スクラルファートの推奨用量は犬1頭に付き0.5–1 gramを経口で 8–12 時間毎の投与が推奨される。




最も一般的に使用される抗生物質は、アモキシシリン、アモキシシリン-クラブラン酸(Clavamox、ファイザー社、ニューヨーク州ニューヨーク)フルオロキノロン系抗菌剤、メトロニダゾール(7.5 mg/kgに減らして口経で1日2回)を含む。
















One Response to “犬の慢性肝炎治療の最新概念 - 4.肝不全合併症の対症療法”

Leave a Reply