Health Canada is warning parents not to give cough and cold medication to children under six-years-old.

Last year, the agency recommended that cough and cold medication shouldn't be given to children under two, unless directed to do so by a health care practitioner.

Health Canada says it is raising the age limit after having conducted further analysis of available information.

The agency provided the following reasons for increasing the cut-off age:

- Recommendations from Canadian and international health professionals and experts that these medicines should not be used in children under 6;

- Body weight and its affect on how medicines work. Some children between the ages of 2 and 6 years may weigh the same as other children who are less than two years old, the most vulnerable group;

- Children under the age of 6 years generally have more colds compared to older children and therefore, are likely to be exposed more frequently to these medications; and

- Younger children are less likely to be able to communicate a potential side-effect from a cough and cold medicine and to ask their parents/caregivers for help in the same way a child over the age of 6 can.

In light of the decision, manufacturers must now show the age warning on all cough and cold medicines for children. They have until fall 2009 to update the labels.

The products must also have "enhanced labelling" for children ages 6 to 12, child resistant packaging, and dosing devices for liquid formulas.

The agency is also reminding parents that the common cold is a viral infection for which there is no cure.

"Cough and cold medicines offer only temporary relief of symptoms such as runny nose, cough, or nasal congestion," says the release.

"Symptoms can also be managed using a variety of non-medicinal measures such as adequate rest, increased fluid intake and a comfortable environment with adequate humidity."