WADA have approved changes for 2010 for doping.  Relevant to us is :

Pseudoephedrine is back on the controlled list.  This is used in many cold and 'flu and hay fever medications and is potentially a performance enhancing stimulant (sprinters, power athletes etc) :

Pseudoephedrine Reintroduced

Another noteworthy amendment is the reintroduction of pseudoephedrine to the List as a specified stimulant – a category of substances that is more likely to result in a sanction of a warning to a two-year ban in case of anti-doping rule violations.

Until 2003, pseudoephedrine was prohibited in sport. Pseudoephedrine was subsequently included in WADA’s Monitoring Program in 2004. The Monitoring Program includes substances that are not prohibited in sport but are monitored in order to detect patterns of misuse.

Results of the Monitoring Program over the past five years have shown a sustained increase in samples containing pseudoephedrine concentrations of more than 75 micrograms per millilitre. The Program indicated clear abuse of this substance with high concentrations in a number of sports and regions. In addition, available literature shows scientific evidence of the performance-enhancing effects of pseudoephedrine beyond certain doses.

Based on literature and results of controlled excretion studies funded by WADA, pseudoephedrine will therefore be reintroduced in the List starting on January 1, 2010, with a urinary threshold of 150 micrograms per millilitre. Given the wide availability of medicines containing pseudoephedrine, WADA’s Scientific Committees and Executive Committee recommended that the reintroduction of pseudoephedrine be accompanied by information and education campaigns by WADA’s stakeholders.

For asthmatics, Ventolin changes, no TUE is required :

Change of Status for Salbutamol

The 2010 List offers a number of changes compared to the 2009 List. In particular, the status of salbutamol, a beta-2 agonist, will change. Salbutamol – a substance considered as specified and therefore more likely to result in a sanction of a warning to a two-year ban in case of anti-doping rule violations – will be permitted under 1,000 nanograms per millilitre. Under the 2010 List, its use by inhalation will no longer require a Therapeutic Use Exemption (TUE) but rather a simplified declaration of use. This measure will allow the handling of salbutamol by anti-doping organizations in a more cost-efficient way.

For both of these drugs I would expect that ASADA will publish guidelines as to the amount one would have to take before they're in danger of crossing the allowable thresholds.