Questions and Answers ENTERRA THERAPY

How large is the Enterra neurostimulator?

The Enterra™ II neurostimulator model 37800 is 2.4 inches (60 mm) long, 2.2 inches (55 mm) high, and 0.5 inches (11.4 mm) thick. It weighs 1.6 ounces (45 grams).

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Will the Enterra neurostimulator eliminate my nausea and vomiting symptoms?

The WAVESS (Worldwide Anti-Vomiting Electrical Stimulation Study1) clinical study of the Enterra neurostimulator used in treating nausea and vomiting associated with gastroparesis* has shown that most, but not all, patients have some relief of their vomiting symptoms.

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If gastric electrical stimulation works for me, when will I notice improvements in my symptoms?

The rate of improvement varies from person to person.

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How long will my neurostimulator battery last?

How long the battery lasts depends on your stimulation settings. Some people need more stimulation, which drains the battery faster, and others need less.

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What will happen when the neurostimulator battery runs down?

Your doctor will need to schedule a surgical procedure to replace the neurostimulator. Enterra II contains a battery indicator that tells your doctor when it is time to schedule a device replacement for continued therapy.

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Can the neurostimulator battery be recharged?

The entire neurostimulator, which contains the battery, must be replaced when the battery runs down. The neurostimulator is not rechargeable.

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Will I be able to turn the neurostimulator on and off?

Only your doctor can turn the neurostimulator on and off with the external clinician programmer.

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Can the Enterra neurostimulator be used during pregnancy?

The safety of neurostimulation for use during pregnancy or delivery has not been established. If you learn, or suspect, that you are pregnant, call your doctor.

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What is a Humanitarian Device?

A humanitarian device is a medical device specially designated by the US Food and Drug Administration (FDA) for use in the treatment of a rare medical condition (fewer than 8000 new cases per year in the United States). The FDA requires that any physician who wishes to use the device to treat a patient must first obtain approval from the hospital's institutional review board. The Medtronic Enterra Therapy system was designated as a device for humanitarian use by the FDA in 1999.

After Enterra Therapy was designated for humanitarian use, Medtronic submitted a Humanitarian Device Exemption (HDE) application to the FDA. This type of application is not required to contain the results of scientifically valid clinical investigations demonstrating that the device is effective for its intended purpose. However, it must contain sufficient information for the FDA to determine that the device does not pose an unreasonable or significant risk of illness or injury and that the probable benefit to health outweighs the risk of injury or illness from its use, taking into account the probable risks and benefits of currently available devices or alternative forms of treatment. Also, the applicant must demonstrate that no comparable devices are available to treat or diagnose the disease or condition, and that the applicant could not otherwise bring the device to market. Once the FDA approved the Humanitarian Device Exemption in 2000, Medtronic was able to manufacture and distribute Enterra Therapy in the United States.

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Abell T, McCallum R, Hocking M, et al. Gastric electrical stimulation for medically refractory gastroparesis. Gastroenterology. August 2003;125(2):421-428.

*Humanitarian Device: The Enterra Therapy system for gastric electrical stimulation is authorized by Federal law for use in treatment of chronic intractable (drug refractory) nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology. The effectiveness of this device for this use has not been demonstrated. What does this mean?

Information on this site should not be used as a substitute for talking with your doctor. Always talk with your doctor about diagnosis and treatment information.