Posted on

well tolerated

The authors systematically treated 94 patients with West syndrome using the same protocol of sodium valproate and steroids, starting with hydrocortisone (HC) orally for two weeks. If seizures stopped, HC was withdrawn; if they persisted, tetracosactrin (TA; synthetic ACTH) was administered for another two weeks then HC was slowly withdrawn. 90 per cent of the symptomatic cases were controlled by HC, the remainder by TA. 65 per cent of symptomatic cases were controlled by HC; this rose to 78 per cent if patients treated by HC then TA were included. At 31 months follow-up, the percentage of favourable results was 72 per cent for cryptogenic and 60 per cent for symptomatic cases. For the latter, best results were obtained in patients with periventricular leukomalacia, postnatal distress and porencephaly. Patients suffering from sequelae of full-term distress or encephalopathy of unknown aetiology were the most resistant.

I agree with Prof Aronson completely. The way well-tolerated is used can be the scientific equivalent of political spin. Whether or not a patient has tolerated a drug is dependent of how tolerant the patient is (to adverse effects) as well as the adverse effects themselves, and is likely to be a function of the perceived benefits. A drug that prevents imminent death is likely to be tolerated even if it does cause your hair to fall out. On the other hand the same adverse event would not be tolerated for drug treatment of a mild headache. Toleration is an individual value judgement, and so the extent to which a patient has “tolerated” a drug can only be established by asking the patient. If a drug is described as well-tolerated the editors should expect some evidence that the patients have been asked appropriate questions about their experience of taking the drug. In the absence of such evidence the term should not be used.

On the other hand, I’m not sure about tolerance either.

It’s not obvious, but “tolerance” comes from the Latin word ferre, to carry, whose principal parts, from different roots, are ferro, ferre, tuli, latum (see BMJ 2000;320:625). And “tolerance” carries several technical meanings.

Pharmacological tolerance can be acquired or natural. Acquired tolerance is reduced sensitivity to a drug, from previous exposure either to it or (cross-tolerance) to another drug. It should not be confused with tachyphylaxis or …