Magnetic Resonance Imaging (MRI) scans are a common diagnostic tool used in modern medicine. While an MRI is not usually painful, some people with severe claustrophobia or conditions that do not allow them to remain still may request or be prescribed a sedative to take before the scan. Sedation for an MRI is not usually total, but instead puts the patient in a lightly sedated state.
An MRI works by aligning the water molecules of the body to create a signal that can be turned into a three-dimensional image of the body. The process requires almost total stillness while in the machine, as moving around will distort the image. Sedation for an MRI can help people with chronic pain relax during the scan, by reducing their need to shift or move.
Sedation before an MRI may also be helpful to people with tics or twitches that are the result of medication or a medical condition, such as restless leg syndrome. A sedative for an MRI may calm the condition for long enough to get the necessary images. Usually, an oral sedative is used for MRI scans, but in more severe cases, an IV-drip sedative or an inhaled sedative may be used to put the patient under a deeper level of sedation.
Another reason that a person might request sedation for an MRI is claustrophobia. The MRI machine usually looks like a narrow tube, prompting reactions in people with a pronounced fear of small places. The scan also can take up to an hour, depending on the amount of images needed, so those with anxiety or claustrophobia issues need to be able to lie still for a long period of time. For those who do not believe they can remain still or who suffer panic symptoms when in small spaces, sedation for an MRI may be useful. In addition to calming the patient, it also will make the test go faster than if the patient moves or panics.
Children may also be required to be sedated for having an MRI. Though a safe and painless scan, the machine and the inability to move may be scary to some younger patients. The fear may be worsened by the fact that a parent cannot be with the child in an MRI room, though most MRI scanners have a microphone that allows the patient to talk to the control room if concerned.
It is important to follow the doctor's instructions carefully when taking sedation for an MRI. Some forms require that a patient not eat or drink for several hours before taking the medication. Since extreme drowsiness is a common side effect, a person under sedation cannot drive home alone and must usually be monitored for a few hours after the procedure for signs of complications.