We studied changes in the hyperuricaemia-associated lipid phenotypes of primary hyperuricaemic-hyperlipidemic patients, none of whom was obese, hypertensive or an alcohol drinker. The patients were monitored for three months during which they were placed on a strict diet. The results obtained showed that phenotype IIB was most frequently associated with hyperuricaemia, followed by phenotypes IV and IIA. Lipid phenotypes were found to change in most patients during the study, even though most of them remained hyperuricaemic-hyperlipidemic. We also determined apoprotein B in each determination and found that over half the patients possessed increased levels of this apolipoprotein. The results confirm that hyperuricaemia is not associated to a unique lipid phenotype since the phenotype of a given patient may change with time, even in the absence of propitiating external factors.