X–rays may be taken in a laboratory, physician’s office or hospital. In general, no special preparation is needed before an x–ray is taken, unless a special dye called a contrast medium is going to be used. Contrast mediums outline a specific body area internally. They can be swallowed, injected into a vein or inserted rectally, and have a dull, opaque appearance on film.   

If a contrast medium will be used, patients may be asked not to eat or drink after midnight before the test, and the physician may make minor changes in how the patient takes medication. The physician will ask about the patient’s history of allergies to screen for a potential allergic reaction to the dye.

A radiology technician or specially trained nurse generally takes x–ray films. At the time of the test, the examiner will ask the patient to remove any objects that may show up on the image (e.g., clothing, jewelry, wigs, watches or dentures). Splints or prosthetic limbs may also be removed in some cases.

Patients should inform the examiner if they have had an x–ray using a contrast dye or barium in the past few days. They should also make sure the examiner is aware of all medications that have been taken recently, including over–the–counter medications.

Female patients should be sure to inform the examiner if they are or may be pregnant because x–rays can be harmful to fetuses in rare cases. In cases where the benefits of the x–ray outweigh the potential risks, pregnant women may wear a lead apron over their abdomen during the test.

A lead apron is also often worn by patients to help protect sex organs from x–rays. In high doses, women’s eggs and men’s sperm can be affected by radiation. However, the risk of this occurring as a result of an x–ray test is extremely low. Women should also inform the examiner if they have an IUD (a form of birth control) implanted.