Parents are being warned about the risk of overdose linked to using teaspoons for giving children medicine.
Teaspoons vary from a capacity of 2.5ml to 7.3ml, according to a study, and parents are urged to use the special spoon provided or measure the liquid in a syringe first.
They are also being reminded to check age-related dosages on the packaging.
Greek and US researchers examined 71 teaspoons and 49 tablespoons collected from 25 households.
They said a parent using one of the biggest teaspoons would be giving their child 192% more medicine than a parent using the smallest teaspoon. Some of the tablespoons were also twice the size of others.
The experts, writing in the International Journal of Clinical Practice, said that not only is there a risk of overdose, but that some youngsters could also be given too little medicine.
They state: "Teaspoons and tablespoons are unreliable dosing devices, and thus their use should no longer be recommended."
Professor Matthew Falagas, Director of the Alfa Institute of Biomedical Sciences in Athens, one of the authors of the study, said: "Paediatric dosages need to be adjusted to age and body weight and, as a result, children are considered to be more vulnerable to dosage errors than adults."