Changes

*'''Diclazuril''': PO, daily for 28 days, approved by FDA for use as top-dress tablet but not commercially available ''Mode of action'': chemically similar to ponazuril but mechanism of action unknown.  ''Efficacy'': one study reported clinical improvement in 58% of cases.(98 in Furr)  ''Potential adverse effects'': none found in one efficacy study.(Furr)  Reported problems in a multi-centre field study included worsening neurologic status and laminitis but these were not proven to be related to treatment. (IVIS 4)

*'''Diclazuril''': PO, daily for 28 days, approved by FDA for use as top-dress tablet but not commercially available ''Mode of action'': chemically similar to ponazuril but mechanism of action unknown.  ''Efficacy'': one study reported clinical improvement in 58% of cases.(98 in Furr)  ''Potential adverse effects'': none found in one efficacy study.(Furr)  Reported problems in a multi-centre field study included worsening neurologic status and laminitis but these were not proven to be related to treatment. (IVIS 4)

*'''Nitazoxanide, NTZ (Navigator, Idexx Pharmaceuticals)''': no longer commercially available in the US.  ''Mode of action'': a member of the 5-nitrothiazole class of antiparasitics that inhibits the pyruvate:ferredoxin oxidoreductase (PFOR) enzyme dependent electron transfer reaction essential for anaerobic energy metabolism.(IVIS 4)  ''Efficacy'': 60% success rate in an FDA-regulated study.(98 in Furr) ''Potential adverse effects'': adverse effects and death at high doses(98), fever, anorexia, diarrhoea, lethargy, depression and laminitis recorded at lower doses.  Toxic signs usally resolve upon cessation of treatment.(Furr)'''''Caution''': 'administration of nitazoxanide can disrupt the normal microbial flora of the gastrointestinal tract leading to enterocolitis.  Deaths due to enterocolitis have been observed while administering the recommended dose in field studies.''''''(IVIS 4)

*'''Nitazoxanide, NTZ ('Navigator', Idexx Pharmaceuticals)''': no longer commercially available in the US.  ''Mode of action'': a member of the 5-nitrothiazole class of antiparasitics that inhibits the pyruvate:ferredoxin oxidoreductase (PFOR) enzyme dependent electron transfer reaction essential for anaerobic energy metabolism.(IVIS 4)  ''Efficacy'': 60% success rate in an FDA-regulated study.(98 in Furr) ''Potential adverse effects'': adverse effects and death at high doses(98), fever, anorexia, diarrhoea, lethargy, depression and laminitis recorded at lower doses.  Toxic signs usally resolve upon cessation of treatment.(Furr)'''''Caution: 'administration of nitazoxanide can disrupt the normal microbial flora of the gastrointestinal tract leading to enterocolitis.  Deaths due to enterocolitis have been observed while administering the recommended dose in field studies.'''''(IVIS 4)