Asthmatics may experience asthma attacks from sulfite fumes as well. Peper has similarly taught asthmatics who wheeze to better control their breathing. Pump inhalers for asthmatics deliver aerosolized drugs into the lungs via the mouth. Cytokines IL-4 and IL-13 gets elevated in lungs of chronically suffered asthmatics. Other medications that can cause problems in asthmatics are angiotensin-converting enzyme inhibitors, aspirin, and NSAIDs. People with pre-existing airway hyperreactivity, such as asthmatics, will react to lower doses of drug. In Canada, for example, up to 75% of asthmatics also have seasonal allergies. There are also increased levels of MMP in the lungs of asthmatics. Caffeine in low doses may cause weak bronchodilation for up to four hours in asthmatics. This restricts its usage, as treating asthmatics could induce bronchospasms. Other benefits would be reduced healthcare costs such as lower levels of asthmatics for example. Asthmatics should take great care when handling this hormone as PGF2a is bronchoconstrictor. Surveys have shown that between 0.5% and 1% of recreational divers are asthmatics. The conservative approach was to arbitrarily disqualify asthmatics from diving. Because of this, it attracted many asthmatics early on.