Bronchitis can be a terrifying condition, and medicine has an armoury of drugs to call into the frontline. Drugs that are regularly used include ribavirin, epinephrine, ipratropium bromide, the beta agonist bronchodilators, inhaled and oral corticosteroids and antibiotics.
Unfortunately, none of them work.
An exhaustive study by the US Agency for Healthcare Research and Quality concluded that there is conflicting evidence for every one of the drug therapies.
Part of the problem is that there is no agreed method of treatment, and so doctors follow their usual practice.
Some few cases respond well to antibiotics, but only if there is an underlying cause of bacterial infection.
There is just as much confusion about diagnosis. Despite the widespread use of chest x-rays, blood counts and other laboratory tests, there is no evidence that suggests that any of these are accurate.
(Source: British Medical Journal, 2003; 361: 939).