THE plastic explosive composition C-4 is commonly known as RDX (Royal Defence Explosive) for its main component. RDX is a white, crystalline powder used as an explosive substance for police, military or civilian purposes. The active ingredient of RDX is cyclonite or hexogen; its chemical formula is cyclotrimethylenetrinitramine or hexahydro-1,3,5trinitro-1,3,5-triazine (Harrell-Bruder and Hutchins 1995). There are few reports of RDX intoxication; reports of RDX intoxication in military personnel (Goldberg and others 1992, Harrell-Bruder and Hutchins 1995, Hett and Fichtner 2002) and civilians (Woody and others 1986) have documented generalised seizures, headaches, nausea, vomiting, hyperexcitability, haematuria and petechial rash. Reported cases of animal intoxication are rare (Berry and others 1983, De Cramer and Short 1992, Gogal and others 2003). While handling explosives during training, police or military working dogs may be exposed to RDX, and may therefore suffer intoxication (Berry and others 1983). Pets and wild animals may be exposed to residues of RDX by ingesting contaminated soil or water (Nipper and others 2001, Gogal and others 2003). The main reported clinical signs of exposure in dogs include generalised convulsions, muscle fasciculation, salivation, vomiting, tachypnoea, dyspnoea and hyperexcitability (Dilley and others 1982, Berry and others 1983, De Cramer and Short 1992). This short communication describes a case of general tonic-clonic seizures, transient blindness and hepatic insult, with full recovery, following the ingestion of RDX by a police working dog. A three-year-old, entire, female labrador retriever police working dog, weighing 25 kg, was referred to the Koret School of Veterinary Medicine Teaching Hospital, Israel, with facial twitches and hypersensitivity, 60 minutes after ingesting a small fragment, described to be the size of a grain of rice, of RDX during training. The dog had been exposed to RDX at least once a week during 14 months of training before this incident, with no apparent adverse effects. The trainer had administered two 30 ml doses of 3 per cent hydrogen peroxide, 15 minutes apart, orally to the dog in order to induce vomiting, and it was referred to the veterinary hospital. White material that was suspected to be RDX residue was observed in the vomitus. On admission, the dog was panting and had a normal body temperature (39·0°C) and pulse (132 bpm). Clinical examination revealed pale mucous membranes and central nervous system (CNS) signs that included facial twitches, confusion and hyperexcitability. For initial emergency management, lactated Ringer’s solution was administered intravenously at a rate of 5 ml/kg/hour. Pretreatment haematology and serum biochemistry were unremarkable. The urine specific gravity was 1·035 and blood casts were seen in the urinary sediment. Thirty minutes after admission, the dog collapsed, exhibited tonic-clonic generalised seizures and became cyanotic. It received 6 mg/kg diazepam (Assival; Biogal) and 12 mg/kg propofol (Diprofol; Taro) intravenously until the seizures ceased. In addition, the dog was given 4 mg/kg phenobarbital (Luminal; Quimica) intramuscularly. An endotracheal tube was placed and the dog received positive-pressure ventilation. Gastric lavage was performed, and white matter that resembled the matter noted by the referring police trainer in the vomitus was seen. After lavage, 1 g/kg activated charcoal was administered through the gastric tube. During the next five hours the dog suffered four more episodes of generalised seizures while anaesthetised; each time it received 0·4 mg/kg propofol intravenously and a constant-rate intravenous infusion of diazepam at 10 mg/100ml 0·9 per cent saline, at a rate of 2 ml/kg/hour, to stop the seizures. Analysis of the arterial blood gases, performed four hours after the dog’s arrival, when it was on 100 per cent oxygen, revealed a pH of 7·32, PO2 of 440·3 mmHg, PCO2 of 42 mmHg and bicarbonate concentration (cHCO3 –) of 21·8 mmol/l. The dog was treated with 5 mg/kg cimetidine (Tagamet; GlaxoSmithKline) administered intravenously every eight hours to protect the gastrointestinal tract from the toxin, 1 mg/kg furosemide (Fusid; Biogal) intravenously every six hours to enhance renal clearance of the toxin, and 8 mg/kg thiamine (Bimeda) intramuscularly every 24 hours to protect the CNS from insult. A urinary catheter was placed to monitor the output of urine, and 25 mg/kg ampicillin (Penibrin; Biochemie) was administered intravenously every eight hours to prevent urinary tract infection. Approximately eight hours after the dog’s arrival at the hospital, oedema developed on its muzzle, around the eyes and in all four limbs. Successive blood tests revealed that the total solids decreased from 70 g/l on arrival to 40 g/l (reference range 54 to 78 g/l). To treat the developing hypoproteinaemia, the dog received 10 ml/kg fresh frozen plasma at a rate of 5 ml/kg/hour. This was followed by administration of hydroxyethyl starch (HAES-steril; Fresenius Kabi) at a rate of 1 ml/kg/hour. Several attempts to disconnect the dog from anaesthetic were unsuccessful, resulting in renewed generalised seizures. The dog remained on anaesthetics for a total of approximately 24 hours. When recovering from anaesthesia, the dog exhibited transient blindness and had no menace response for a period of approximately 12 hours. The pupillary light response and palpebral reflex were intact in both eyes. Over the following 48 hours the dog progressed to complete clinical recovery. Routine blood biochemistry, conducted at the hospital’s laboratory 24 hours after the dog was admitted, revealed a low albumin concentration of 20·4 g/l (reference range 28·3 to 38·3 g/l) and slight hyperbilirubinaemia (24·62 μmol/l, reference range 0·34 to 9·23 μmol/l). Two days later, bilirubin increased to 105·17 μmol/l, alkaline phosphatase (AP) was elevated (975 iu/l, reference range at 37°C 4 to 140 iu/l, ) alanine aminotransferase (ALT) increased to 166 iu/l (reference range at 37°C 5 to 103 iu/l) and aspartate aminotransferase (AST) increased to 136 iu/l (reference range at 37°C 9 to 47 iu/l). Because of the biochemical evidence of hepatic insult, the dog was supplemented with 2 mg/kg vitamin K, administered orally every 24 hours, 4·5 mg/kg zinc sulphate (Avazinc; Rekah) orally every 12 hours as an antioxidant, and 1·25 ml multivitamins (Duphafral Multi; Fort Dodge) administered intramuscularly every 24 hours. The dog was discharged four days after it had been admitted. Four days later, complete blood chemistry, conducted in a different (government) laboratory, revealed an albumin concentration of 29 g/l (reference range 26 to 40 g/l), AP 1614 iu/l (reference range at 37°C 13 to 190 iu/l), ALT 485 iu/l (reference range at 37°C