A new study has pointed out that allergy shots which alleviate symptoms of asthma may have side effects.
The side effects could range from a stuffy nose to fatal anaphylactic shock.
The study shows about 30 percent of asthma patients experience improved breathing after receiving a series of injections that desensitize their immune systems to specific irritants.
The number of patients experiencing systemic reactions of any severity nears 20 percent, the reviewers said, although they noted that more than eight percent of patients receiving placebo experience similar reactions.
"Whilst inhaled corticosteroid therapy remains the mainstay of asthma management, any reduction in this type of treatment while maintaining good asthma control would be welcome," the authors wrote.
The review provides evidence to help patients and their doctors have a "sensible discussion" about the benefits versus risks of immunotherapy, said co-author Michael Abramson of Monash University.
Immunotherapy is most risky for patients with poorly controlled asthma and people with treatment-resistant asthma are not candidates for allergy shots," said Harold Nelson of National Jewish Health.