Transdermal patches (adhesive patches placed on the skin) may also be used to deliver a steady dose through the skin and into the bloodstream. Testosterone-containing creams and gels that are applied daily to the skin are also available, but absorption is inefficient (roughly 10%, varying between individuals) and these treatments tend to be more expensive. Individuals who are especially physically active and/or bathe often may not be good candidates, since the medication can be washed off and may take up to six hours to be fully absorbed. There is also the risk that an intimate partner or child may come in contact with the application site and inadvertently dose himself or herself; children and women are highly sensitive to testosterone and can suffer unintended masculinization and health effects, even from small doses. Injection is the most common method used by individuals administering AAS for non-medical purposes. 
A version of this article appears in print on October 13, 2013, on page A 1 of the New York edition with the headline: The Soaring Cost of a Simple Breath. Get Free Email Alerts on These Topics Asthma Drugs (Pharmaceuticals) Prices (Fares, Fees and Rates) Series Inside Health » Too Hot to Handle Arts » The Harmony of Liberty Opinion » Should Beach Privatization Be Allowed? Room for Debate asks whether shorefront homeowners should have to open their land to all comers.