What action do sympathomimetic drugs have in the body?

A) Hypothalamus and the medulla: While the hypothalamus and medulla play critical roles in regulating autonomic functions and overall sympathetic nervous system activity, the primary origin of the sympathetic nervous system's neural impulses comes from the spinal cord, specifically in the thoracic and lumbar regions. The hypothalamus and medulla are involved in coordinating and regulating sympathetic activity rather than being the origin of the impulses themselves.

B) Cranium and sacral area of the spinal cord: The cranium and sacral regions are primarily associated with the parasympathetic nervous system, not the sympathetic nervous system. The parasympathetic nervous system's nerve fibers arise from the brainstem and the sacral region, while the sympathetic fibers originate from the thoracic and lumbar areas.

C) Thoracic and lumbar section of the spinal cord: The sympathetic nervous system originates in the thoracolumbar region of the spinal cord, which includes the thoracic and lumbar segments (T1-L2). These regions house the preganglionic neurons whose axons exit the spinal cord and synapse in sympathetic ganglia, leading to the sympathetic effects on organs and tissues. This makes the thoracic and lumbar sections the correct location for the origin of SNS impulses.

D) Nerve membrane: The nerve membrane, or the cellular membrane of individual neurons, is not the location where impulses originate. The origin of the impulses is in the central nervous system (CNS), specifically in the spinal cord for the sympathetic system, not at the level of the individual nerve membranes.

A) Suspect worsening of the anxiety disorder:
While it is possible that the patient's anxiety disorder is worsening, the more likely explanation for the reduced effectiveness of lorazepam is the development of drug tolerance. Over time, patients may require higher doses of a medication to achieve the same therapeutic effect, especially with medications like lorazepam that are used chronically.

B) Contact the provider to discuss changing to another benzodiazepine:
Changing to another benzodiazepine might be an option, but it is more likely that tolerance to lorazepam is the cause of the reduced effect, not an issue with the specific drug. Tolerance is common with long-term use of benzodiazepines, and switching drugs may not address the underlying issue. The first step would be to assess the current medication regimen and discuss possible adjustments with the provider.

C) Understand that the patient has developed tolerance to this drug:
Tolerance occurs when the body becomes accustomed to the effects of a medication over time, requiring higher doses to achieve the same therapeutic effect. This is a common phenomenon with benzodiazepines like lorazepam, which are often used for long periods to manage anxiety. As the patient has been taking lorazepam for six months, this reduced effectiveness is likely due to the development of tolerance, rather than a worsening of the anxiety disorder.

D) Notify the provider and discuss increasing the dose of lorazepam:
While increasing the dose of lorazepam could temporarily relieve symptoms, it is not the most appropriate first step. The nurse should first consider the possibility of tolerance and discuss this with the provider before increasing the dose. Long-term increases in benzodiazepine dosages can increase the risk of side effects, dependency, and withdrawal symptoms.