The prescribing of medicines for ambulant children below 14 years of age has been compared between Tenerife (Spain) and Sweden. Data obtained from a random sample of 1327 children in a prospective study in Tenerife were compared with data from 3901 children in a Swedish survey linking diagnosis and therapy. Upper respiratory tract infection was the main diagnosis in both countries and antibiotics was the most frequently prescribed drug group (28.2% in Tenerife and 28.8% in Sweden). Half of the children in Sweden did not receive any medication, but only 10% of those in Tenerife did not receive a prescription. Children who received a prescription on average got 1.4 drugs in Sweden and 2.3 in Spain. Amongst the ten most commonly prescribed products in Sweden there were 11 active pharmacological principles as compared to 25 in Spain. These most frequently used preparations accounted for two thirds of all the prescriptions for children in Sweden and one third in Tenerife. In conclusion, drugs were significantly more often used to treat paediatric outpatients in Tenerife than in Sweden. The prescribing physician in Spain also chose a wider variety of drugs and more commonly used fixed combination products.