Table 3 Details of feline population size, seizure frequency, treatment time, doses of AED(s), seizure frequency reduction after AED initiation, 95% CI for the successful and affected cases and evidence statements for each study
From: Systematic review of antiepileptic drugs’ safety and effectiveness in feline epilepsy
References | Engel et al. [20] (ELAS 1) | Engel et al. [20] (ELAS 2) | Engel et al. [20] (Clinical trial) | Center et al. [45] | Hughes et al. [46] | Schwarz-Porsche & Kaiser, [44] | Sawchuk et al. [47] | Schwarz-Porsche & Kaiser, [44] | Roye et al., [48] | Schwarz-Porsche & Kaiser [44] |
|---|---|---|---|---|---|---|---|---|---|---|
AED evaluated | Imepitoin | Diazepam | Primidone | Phenytoin | ||||||
2nd AED | - | - | - | - | - | Diazepam | ||||
3rd AED | - | - | - | - | - | - | ||||
4th AED | - | - | - | - | - | - | ||||
No of cats | 6 | 6 | 8 (7 were evaluated for the safety profile) | 11 (non-epileptic cats) | 5 (non-epileptic cats) | NA | 11 | 6 | 4 (non-epileptic cats) | 2 |
Age of cats at seizure onset (years) | NA | NA | median 4; mean 6.3; range 1-15 | NA | range 1-12 | range 0.2-9 | NA | range 0.2-9 | NA | range 0.2-9 |
Period of treatment or follow-up (months) | 1 | 1 | at least 2 (for the seizure-freedom cases the period was mean 4; range 2-7.5) | 0.5 | 0.25-0.5 | 6 | 3 | range 5-108 | 0.8 | >3-9 |
Dose of AED(s) (mg/kg) | 30 PO BID | 40 & 80 PO BID | median 30; mean 27.92 PO BID | 1.25-2 PO SID or BID | 0.23-0.82 PO SID | 0.5-2 PO (divided in 3 daily doses) | 20 mg/kg PO BID | 40-50 PO (divided in three daily doses) | 10 PO and intramuscularly SID | 1.5 PO SID |
Serum levels of AED(s) | NA | NA | NA | NA | NA | NA | 4.1 μg/mL | NA | 25-35 μg/mL | 6.5-17 μg/mL |
Pre-treatment SF (seizures/month or year) | NA | NA | Median 20; mean 57.71; range 2-200 | NA | NA | NA | NA | NA | NA | |
Post-treatment SF (seizures/month or year) | NA | NA | Median 1.5; mean 19.43; range 0-100 | NA | NA | NA | NA | NA | NA | NA |
No of cats that were failures | NA | NA | 3/8 (37%) | NA | NA | - | NA | 2/6 (33%) | NA | 1/2 (50%) |
No of cats with >0% - <50% reduction in SF | NA | NA | - | NA | NA | 20% | NA | - | NA | - |
No of cats with ≥50% - <100% reduction in SF | NA | NA | 1/8 (13%) | NA | NA | 40% | NA | 2/6 (33%) | NA | - |
No of cats with 100% reduction in SF | NA | NA | 4/8 (50%) | NA | NA | 40% | NA | 2/6 (33%) | NA | 1/2 (50%) |
95% CI of successfully treated cases | NA | NA | 30-86% | NA | NA | NA | NA | 30-90% | NA | 9-90% |
Prevalence of adverse effects | 0 % (apart from intermittent/rare vomiting) | 0 % (apart from intermittent/rare vomiting, hypersalivation and slightly decreased appetite) | 5/7 (71%) | NA | NA | 0% | 11/11 (100%) | 1/6 (17%) | 4/4 (100%) | 2/2 (100%) |
95% CI of cases that developed adverse effects | NA | NA | 36-92% | NA | NA | 0% | 100% | 3-56% | 100% | 100% |
Body system affected and adverse effects | NA | NA | Neurological (sedation (2), ataxia (1)), GI (anorexia (2), PP (1), vomit (2), hypersalivation (1)), PD (1), decreased drinking (1) | Neurological (sedation(5), ataxia(5)), GI (acute hepatic necrosis(11), anorexia (5)) | GI (acute hepatic necrosis) | NA | Neurological (sedation, ataxia) | Neurological (sedation), GI (anorexia, weight loss) | Neurological (sedation, ataxia) GI (anorexia) | GI (anorexia), ClinPath (increased liver enzymes) |
Most common adverse effects | Intermitent vomit | Intermittent vomit | Sedation, vomit, decreased appetite | NA | NA | NA | NA | NA | NA | NA |
Adverse effect type | I | I | I | I & II | II | NA | I | NA | I | I |
Proportion of specific adverse effects for each AED based on all study reports | Type I: sedation (1/3; 33%) and ataxia (1/3; 33%), GI signs, i.e. anorexia (1/3; 33%), PP (1/3; 33%), vomiting (1/3; 33%), hypersalivation (1/3; 33%), and PD (1/3; 33%) or decreased water consumption (1/3; 33%) | Type I: sedation and ataxia | Type I: sedation (2/2; 100%), ataxia (1/2; 50%), anorexia (1/2; 50%) and weight loss (1/2; 50%) | Type I: anorexia (2/2; 100%), sedation (1/2; 50%), ataxia (1/2; 50%), increased liver enzymes (1/2; 50%) | ||||||
Type II: acute hepatic necrosis | ||||||||||
One study reported no adverse effects | ||||||||||
Proportion of specific adverse effects for each AED based on the total affected population | Sedation (2/19; 11%), anorexia (2/19; 11%), vomiting (2/19; 11%), ataxia (1/19; 5%), PP (1/19; 5%), hypersalivation (1/19; 5%), PD (1/19; 5%) and decreased drinking (1/19; 5%) | NA | Sedation (12/17; 71%), ataxia (11/17; 65%), anorexia (1/17; 6%) and weight loss (1/17; 6%) | Anorexia (6/6; 100%), sedation (4/6; 67%) ataxia (4/6; 67%) and increased liver enzymes (2/6; 33%) | ||||||
Weak and good level of evidence for imepitoin’s efficacy and safety profile, respectively | Weak level of evidence for diazepam’s efficacy and safety profile | Weak level of evidence for primidone’s efficacy and safety profile | Weak level of evidence for phenytoin’s efficacy and safety profile | |||||||