クリンダマイシン
クリンダマイシンは、獣医学で広く使用されている広域スペクトルの**リンコサマイド系抗生物質**です。多くの嫌気性菌、グラム陽性好気性球菌（ブドウ球菌やレンサ球菌など）、および特定の原虫（トキソプラズマ、ネオスポラ、バベシアなど）に対して高い有効性を示します。 **臨床のポイント：** * **優れた組織移行性：** 骨、滑液、膿瘍、白血球に高濃度で移行するため、**骨髄炎**、**歯科感染症**、**深在性膿皮症**の第一選択薬となります。 * **トキソプラズマ症：** 犬や猫の臨床的トキソプラズマ症の主要な治療薬です。 * **草食動物への毒性：** 致命的なクロストリジウム性腸炎を引き起こすリスクがあるため、後腸発酵動物（馬、ウサギ、齧歯類）および反芻動物への使用は厳禁です。 * **食道狭窄のリスク：** 猫において、カプセルや錠剤をそのまま（水なしで）飲ませると、重度の食道炎や狭窄を引き起こす可能性があります。経口固形薬の投与後は必ず水や食事を与えてください。
作用機序: Clindamycin acts by binding to the **50S ribosomal subunit** of susceptible bacteria. * **Mechanism:** It inhibits peptide bond formation (transpeptidation) → blocks bacterial protein synthesis. * **Effect:** It can be either **bacteriostatic** or **bactericidal**, depending on the drug concentration at the infection site and the specific susceptibility of the organism. * **Resistance:** Complete cross-resistance occurs between clindamycin and lincomycin, and partial cross-resistance occurs with macrolides (like erythromycin) due to overlapping ribosomal binding sites.
動物種別の用量
- Susceptible bacterial infections · 5-10 mg/kg · PO · q12h
- Infected wounds, abscesses and dental infections · 11-33 mg/kg · PO · once a day (q24h) · Maximum 14 days · Do not treat acute infections for more than 3-4 days if no clinical response is seen.
- Sepsis · 11 mg/kg · IV · q12h
- Anaerobic infections · 5-10 mg/kg · PO, IV · q12h
- Intra-abdominal sepsis · 5-11 mg/kg · IV, SC, PO · q8-12h · 5-7 days · Combined with gentamicin or a parenteral 3rd generation cephalosporin or enrofloxacin
- Pancreatitis · 5-11 mg/kg · IV, SC, PO · q8-12h · 3-5 days
- Susceptible respiratory infections · 10-15 mg/kg · PO, SC · q12h
- Surgical prophylaxis for gram-positive aerobes and anaerobic coverage · 5-11 mg/kg · PO · once · 16-60 minutes preoperatively
- Toxoplasmosis (to decrease zoonotic risk by reducing shedding period) · 25-50 mg/kg · PO · daily
- Clinical toxoplasmosis · 10 mg/kg · PO · q12h · at least 28 days · Institute supportive care as needed.
- Enteroepithelial toxoplasmosis · 8-16 mg/kg · PO, SC · q8h · 14-28 days
投与経路
禁忌
- Horses
- Rabbits
- Hamsters
- Chinchillas
- Guinea pigs
- Ruminants
- Patients hypersensitive to lincosamides
- Neonatal small animals (generally avoided)
- Known hypersensitivity to lincosamides
有害事象
- Gastroenteritis (emesis, loose stools, bloody diarrhea)
- Esophageal injuries (esophagitis, strictures) in cats if dry-pilled
- Hypersalivation or lip smacking in cats after oral administration
- Pain at IM injection site
- Mild, clinically insignificant increases in liver enzymes (AST, ALT, ALP)
- Colitis
- Vomiting
- Diarrhoea
- Oesophagitis (especially in cats)
- Oesophageal stricture (especially in cats)
薬物相互作用
- Cyclosporine · Clindamycin may reduce cyclosporine levels
- Erythromycin · In vitro antagonism when used with clindamycin; concomitant use should probably be avoided
- Neuromuscular blocking agents (e.g., pancuronium) · Clindamycin possesses intrinsic neuromuscular blocking activity and should be used cautiously with other neuromuscular blocking agents
- Non-depolarizing muscle relaxants (e.g., tubocurarine) · May enhance the neuromuscular blocking effect · major
- Neostigmine · May antagonize the effects of neostigmine · moderate
- Pyridostigmine · May antagonize the effects of pyridostigmine · moderate
- Macrolides (e.g., erythromycin) · Antagonistic antimicrobial effects due to competing binding sites · major
- Chloramphenicol · Antagonistic antimicrobial effects due to competing binding sites · major
- Other lincosamides · Antagonistic antimicrobial effects · major
- Tubocurarine (and other non-depolarizing muscle relaxants) · May enhance the neuromuscular blocking effect · moderate
- Lincomycin · Complete cross-resistance and antagonistic effect · major
モニタリング
- Clinical efficacy
- Adverse effects; particularly severe diarrhea
- Periodic liver and kidney function tests and blood counts if therapy persists for more than 30 days
- Gastrointestinal signs (vomiting, diarrhoea)
- Hepatic and renal function in patients with pre-existing impairment
過量投与
There is little information available regarding overdoses of this drug. * In dogs, oral doses of up to **300 mg/kg/day** for up to one year did not result in toxicity. * Dogs receiving **600 mg/kg/day** developed anorexia, vomiting, and weight loss.
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。