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The recent reports from Hong Kong, Taiwan, China and Korea were reviewed to determine the causes and prospects for prevention of herb-induced aconite poisonings. The contributory factors included overdose (use of greater than the recommended doses), faulty processing (after harvest and during decoction), use of tincture (herbal medicinal wine), use of crude aconite roots (for preparing decoction, proprietary medicines and tincture), lack of standardisation in processing of aconite roots and preparation of tincture and proprietary medicines, unsupervised use of aconite roots and contamination or mix-up with aconite roots. As tincture (herbal medicinal wine) made from aconite roots contains a much larger amount of Aconitum alkaloids, the public should be strongly discouraged from making their own and taking it by mouth. Aconite roots should only be used after post-harvest processing and proper decoction. The public should be educated on the hazards from unsupervised use and improper decoction of processed aconite roots. There should be regular publicity measures to promote awareness among the herbalists and to publicise the risk of serious cardiotoxicity if the recommended doses of processed aconite roots are exceeded. The processing of aconite roots and their proprietary preparations should be standardised. Quality control of processed aconite roots and their proprietary preparations should be strengthened. National reporting or monitoring systems can be used to identify the causes of aconite poisonings and assess the impact of preventive measures.

1 Colchicine is a highly active alkaloid used in the treatment of gouty arthritis and pseudogout. In over dose colchicine inhibits cell division effecting organs with a high rate of cell turn-over, such as the gastrointestinal tract and bone marrow. Early fatality results from cardiovascular collapse and respiratory failure, however pancytopenia and overwhelming septicaemia can occur later. 2 We describe a case of suicidal ingestion of 25 - 30 mg of colchicine in a previously healthy 43-year-old woman. Initial symptoms were mainly gastrointestinal. By day 5 she had developed severe pancytopenia and early sepsis, which were successfully treated using granu locyte colony stimulating factor (G-CSF) 600 μg s.c. 3 In vitro G-CSF is produced by the haematopoietic system. However, G-CSF can now be produced by recombinant DNA cloning technology and thus is available clinically. 4 There is no recognised antidote for colchicine poison ing and treatment is symptomatic. Fab fragments may have a promising future in eliminating colchicine from the body, but are currently not clinically available. In those patients that survive the initial phase of poisoning, G-CSF offers an effective method of treating the pancytopenia and preventing overwhelming septi caemia. Daily monitoring of the patient's haematolo gical status is strongly recommended.

Little is known about the incidence and pattern of poisonings in Hong Kong. Hence, adults (subjects aged ≥ 15 years) and children (subjects aged ≤ 14 years) hospitalized in the Princess Margaret Hospital in 1994 with ICD codes of 960-977 (medicinal poisonings) or 980 - 989 (non-medicinal poisonings) were studied. This is the main general hospital with a 24-hour emergency department for the 0.68 million people living in the New Territories South. Sex and age specific rates per 100 000 population were calculated. The incidence of poisoning in 1994 was 113.5/100 000. The incidence was higher in males than in females (130.0 vs 96.4/100 000). Poisoning was more common in adults than in children (128.8 vs 44.9/100 000). Subjects with medicinal poisonings were predominantly young females and hypnotics/sedatives were the main agents involved. In contrast, males aged 35-64 years predominated in non-medicinal poisonings, which were mostly related to alcohol. In children, medicinal poisonings were more common than non- medicinal poisonings (24.9 vs 20.2/100 000). All of the nine deaths were adults.

1 After ingestion, Dettol liquid (4.8% chloroxylenol, pine oil, isopropyl, alcohol), a common household disin fectant, can cause central nervous system depression and corrosion of the oral mucosa, larynx and the gastrointestinal tract. The main risk from Dettol poisoning is pulmonary aspiration, leading to pneu monia, adult respiratory distress syndrome (ARDS) and/or sudden cardiorespiratory arrest. 2 To determine to what extent pulmonary aspiration in Dettol poisoning could be prevented, 13 patients treated in a general teaching hospital in Hong Kong were studied. Their clinical details were compared with those of control Dettol poisoning cases without pulmonary aspiration in order to identify possible risk factors for this complication. 3 At presentation, evidence of pulmonary aspiration was present in eight of the 13 patients prior to gastric emptying, but the use of gastric lavage without adequate protection of the airways could have aggravated the problem in three. In two other patients, evidence of aspiration was only present after gastric lavage was performed. The consequences of pulmon ary aspiration were pneumonia ( n=10), ARDS ( n=2), acute exacerbation of asthma or chronic obstructive airway disease (n=2) and sudden cardiorespiratory arrest ( n=1). Three patients with aspiration pneumo nia ( n=2), ARDS ( n=1) and/or sudden cardiorespira tory arrest ( n=1) died. 4 Compared with the controls, the median amount of Dettol ingested was considerably larger (400 vs 150 ml), vomiting (100% vs 72.6%) and drowsiness/ confusion (69.2% vs 19.4%) occurred more often. 5 Amongst the 13 patients with Dettol poisoning and pulmonary aspiration, gastric lavage using the naso gastric tube technique without adequate production of the airways had been responsible for the occurrence or worsening of aspiration in two and three patients, respectively. Thus, gastric lavage particularly when using a nasogastric tube appeared to carry more harm than benefits in patients with Dettol poisoning. If the procedure is considered necessary, say because of the concomitant ingestion of the other poisons, the air ways must first be well protected and the orophar yngeal aspiration and lavage technique using a wide bore Jacques tube is recommended. 6 Comparison with a control group has identified other risk factors for pulmonary aspiration: the amount of Dettol ingested, the occurrence of vomiting, drowsi ness or confusion.

Methyl salicylate (oil of wintergreen) is widely available in many over-the-counter liniments, ointments, lotions or medicated oils for the relief of musculoskeletal aches and pains. Ingestion of methyl salicylate poses the threat of severe, rapid-onset salicylate poisoning because of its liquid, concentrated form and lipid solubility. Excessive usage of these preparations in patients receiving warfarin may result in adverse interactions and bleedings. Methyl salicylate in topical analgesic preparations may cause irritant or allergic contact dermatitis and anaphylactic reactions. Physicians should fully appreciate the potential dangers from topical preparations containing methyl salicylate.

A 43-year-old woman complained of colicky abdominal pain, followed by numbness, myalgias, and muscle weakness in the four limbs after eating a grouper (Epinepheius spp.). She presented to our hospital 36 hours later with increased myalgias, muscle weakness, and malaise. On examination, the muscle power and sensation in her four limbs appeared to be normal. She was given an intravenous infusion of mannitol 20% (200 ml over 1 hour) and an intramuscularinjection ofdiclofenac (75mg).Hermyalgias then improved andshe was discharged. She presented to our hospital again 1 week later with poor appetite, malaise, numbnessofthefourlimbs,andincreasedmuscleweakness. On examination, the muscle weakness was more marked in the lower limbs (4+/5) than in the upper limbs (5 /5) and proximally than distally. She also had some difficulty in getting up from a squatting position. She was given another intravenous infusion of mannitol 20% (200 ml over 1 hour), following which there was subjectively slight improvement inhermuscleweakness.Herplasmacreatinephosphokinase level was normal. Electromyography performed 4 weeks later revealed no abnormalities. When she was reviewed 45 days after the consumption of the grouper, her muscle weakness and malaise had improved considerably. She could then stand up from a squatting position. However, mild impairment of finger grip was still present. Chronicity of neurological features in other reported cases (e.g., chronic fatigue, relapse of symptoms after exposure to ciguateric fish or alcohol, and peripheral neuropathy) may also indicate a lengthy persistence of ciguatoxins in the body.

In this retrospective study, we determined the clinical value of screening for paracetamol in 294 Chinese patients with acute poisoning presenting to the general medical wards at the Prince of Wales Hospital between January 1992 and June 1993. Of the 86 patients suspected of having ingested paracetamol, eight had levels above the recom mended 'treatment line'. Of the 208 patients with no sus pected paracetamol ingestion, four were found to have ele vated but non-toxic plasma levels. The incidence of missed, potentially serious paracetamol poisoning in our patients with no suspected paracetamol ingestion is extremely uncommon. Routine screening of all patients with acute poisoning for toxic plasma paracetamol con centrations is therefore not indicated and should never be a substitute for thorough history taking and physical examination.

The incidence of adverse reactions to intravenous N-acetylcysteine (NAC) was studied in 56 Chinese patients with paracetamol (acetaminophen) poisoning. Eight (14%) patients developed a skin rash (n= 7) or fever (n= 1) mostly during the initial high dose infusion of the antidote. In four subjects (three with toxic plasma paracetamol levels), the infusion was continued without a worsening of the adverse reaction. NAC was discontinued in the remaining four subjects in whom the paracetamol levels were subsequently found to be non-toxic. Intravenous chlorpheniramine was given to six subjects. All eight subjects completely recovered. In the dose that is recommended for the treatment of acute paracetamol poisoning, intravenous NAC is generally safe in Chinese but mild side effects are common. We recommend that the initial loading dose is given over 60 rather than 15 min.

`Maqianzi’ (the dried ripe seed of Strychnos nux-vomica L.) contains 1.0–1.4% each of strychnine and brucine. After processing to reduce its toxicity, `maqianzi’ was used as a herbal remedy for rheumatism, musculoskeletal injuries and limb paralysis. A 42-year old woman with neck pain was prescribed 15 g of `maqianzi’ to be taken in two doses at 7 hours apart, although the recommended dose was 0.3–0.6 g. She was apparently well after drinking the first of two bowls of `maqianzi’ decoction. One hour after she drank the second bowl of herbal decoction, she suddenly developed tonic contractions of all her limb muscles and carpopedal spasm lasting 5 min, difficulty in breathing, chest discomfort and perioral numbness. The second bowl of decoction probably became more concentrated because of evaporation of water during continued boiling and contained a larger amount of `maqianzi’. On arrival in the hospital 1 hour later, she complained of muscle pain and tiredness. She was found to have hyperventilation and weakness of four limbs, with muscle power of grade 5–/5. All her symptoms gradually subsided over the next few hours. This case illustrated that `maqianzi’ can cause strychnine poisoning even after processing, especially when the recommended dose is greatly exceeded. In any patient with `unexplained’ muscle spasms or convulsions, strychnine poisoning should be included in the differential diagnosis and they should be asked about the use of herbal medicines.

1 To determine if the risk of aspiration is increased in 'Dettol' (4.8% chloroxylenol, pine oil and isopropyl alco hol) poisoning and the factors that may be responsible, a study was made of 89 patients and 89 matched control subjects with other forms of poisoning admitted to the Prince of Wales Hospital, Hong Kong. 2 Aspiration was more common in patients with Dettol poisoning (8% vs 3%, P = 0.16). There were more control subjects with drowsiness at presentation (54% vs 24%, P < 0.0001), but the use of gastric lavage (88% vs 64%, P < 0.001) and the occurrence of vomiting (62% vs 17%, P < 0.0001) were more common in patients with Dettol poisoning. 3 Our findings suggest that Dettol poisoning may be asso ciated with an increased risk of aspiration. This increase in risk may be related to the use of gastric lavage and the common occurrence of vomiting in patients with Dettol poisoning.

1 Dettol liquid (chloroxylenol 4.8%, pine oil, isopropyl alcohol), a household disinfectant, has a corrosive action on the gastrointestinal mucosa when swallowed. The inci dence of upper gastrointestinal haemorrhage and gastro scopic findings following Dettol poisoning was studied in 89 patients. 2 Five patients (5.6%) developed minor haematemesis, in the form of coffee-coloured or blood-stained vomitus. One patient had a gastroscopy performed on the day after admission, showing signs of chemical burns in the oesoph agus and stomach. Gastroscopy was performed in one other patient on day 11 to rule out oesophageal stricture; the patient was normal. All patients completely recovered. 3 The data from this study suggest that upper gastroin testinal haemorrhage following Dettol poisoning tends to be mild and self-limiting. Gastroscopy, which may increase the risk of aspiration in patients with impaired consciousness, is not required unless other causes of gas trointestinal bleeding are suspected.