Neurotransmitter-based diagnosis and treatment: A hypothesis (Part 2)

Impression. Mr. G shows multiple symptoms associated with norepinephrine excess. It is important to avoid caffeine intake in patients with clinical signs of excessive norepinephrine. Beta-blockers and alpha-2 agonists work well in patients such as Mr. G. Benzodiazepines indirectly decrease norepinephrine activity, but need to be used carefully due to the potential for misuse and addiction. In particular, short-acting benzodiazepines such as alprazolam and lorazepam must be avoided due to the induction of CNS instability with rapidly changing medication blood levels. Chlordiazepoxide may be a good choice for a patient such as Mr. G because it has the fewest adverse effects and the lowest abuse potential compared with other benzodiazepines. Avoid SNRIs in such a patient. Using mood-stabilizing antipsychotic medications may be especially warranted in treating Mr. G’s depression and pain.

Norepinephrine deficiency (Table 2^16,26,31-39)

Two years ago, Ms. A was diagnosed with chronic fatigue³¹ and fibromyalgia. She also had been diagnosed with depression and attention-deficit/hyperactivity disorder (ADHD). She presents with concerns of “brain fog,” no energy, low sex drive, and daytime sleepiness.^33,35 Allodynia is widespread.^16,36,37 Ms. A suffers from bulimia; she eats once a day but is still overweight.²⁶ She has orthostatic hypotension in addition to baseline low blood pressure and bradycardia.^16,38,39 Her pupils are almost pinpoint, even when she does not take opioid medications.¹⁶ Her skin is dry and her hair is brittle; deep tendon reflexes are weakened, and her muscle tone is decreased.¹⁶ Ms. A’s constant low mood drives her to drink excessive amounts of caffeine, which she says “helps with daytime sleepiness but does not last”^32,33 and causes heart rhythm problems³⁸ and dyspepsia.¹⁶ She sees that her headaches and body pain are associated with her caffeine intake, but refuses to stop taking caffeine. Her low interest in life and general passivity have caused her many problems, though the problems themselves do not make her feel much.^31,32,39 She is rather indifferent to pleasurable activities, including sex.³¹ Her response to exciting experiences is blunted,³² but she is still frequently tearful.³⁴ Ms. A’s mood does not improve with selective serotonin reuptake inhibitors; she has tried many. She says that she would not come to see a physician, but “my mom told me to.” She resents that her family thinks she is lazy^31,32,39 and blames her ADHD for underperformance in life.^32,33 Ms. A has a family history of chronic pain and Alzheimer disease, and the longer she experiences pain, the worse her memory.³⁵

Comment. As mentioned earlier, because of the norepinephrine/dopamine relationship, symptoms of excess dopamine overlap with symptoms of norepinephrine deficiency.

Impression. Ms. A shows multiple symptoms associated with norepinephrine deficiency. The use of noradrenergic antidepressants (such as SNRIs and mirtazapine)²⁶ and stimulants may be warranted. Physical exercise, participating in social activities, massage, acupuncture, and family support may help with Ms. A’s pain as well as her depression, as might vasopressors.

In Part 3, we will address gamma aminobutyric acid and glutamate.

Bottom Line

Both high and low levels of endorphins and norepinephrine may be associated with certain psychiatric and medical symptoms and disorders. An astute clinician may judge which neurotransmitter is dysfunctional based on the patient’s presentation, and tailor treatment accordingly.

Related Resources

• Arbuck DM, Salmerón JM, Mueller R. Neurotransmitter-based diagnosis and treatment: a hypothesis (Part 1). Current Psychiatry. 2022;21(5):30-36. doi:10.12788/cp.0242

Drug Brand Names

Alprazolam • Xanax
Chlordiazepoxide • Librium
Lorazepam • Ativan
Mirtazapine • Remeron