In some patients who have drug allergy, it is possible that such medications can be used if there is an absolute need for it. In these situations, patients have to go through a drug desensitization process. Drug desensitization is a process of inducing temporary unresponsiveness to the allergic drug. It is done by introducing small amounts of the allergic drug with increasing dose over a fixed time interval until a full therapeutic dose is obtained. This process is used to prevent patients from developing anaphylaxis for the drug in question. It is only a temporary measure and does not induce tolerance for life. The process carries a high risk of severe anaphylaxis so it is done in a hospital ICU unit where close supervision is needed. Common medications that are needed for desensitization are aspirin, antibiotics, biologic drugs e.g. Enbrel®, Humira®, Remicade®, Rituxan®... that are used in several rheumatologic diseases.