What is Reboxetine (Edronax)?

Reboxetine is one of the most controversial drugs and a mystery to the scientific community. Starting with the basics, reboxetine is a type of antidepressant known as a selective noradrenaline reuptake inhibitor (NARI). It’s not currently available in the United States, but in Europe, where it is sold, it goes by the names Edronax, Norebox, Prolift, Solvex, Davedax or Vestra, and has been met with a lot of skepticism.

What Is Reboxetine (Edronax) Used For?

As the first selective norepinephrine (noradrenaline) reuptake inhibitor, reboxetine has been used in the treatment of depression, mainly acute depression and major depression and for maintenance for people who have responded well to using it.

How Does Reboxetine Work?

Some would argue that it doesn’t work to treat depression—and that is what the controversy and the mystery is all about. In a study that reviewed thirteen different large-scale studies of how well reboxetine works, researchers found it’s ineffective and has potentially harmful side effects.

The problem is: it works perfectly in animal models. New drugs go through rigorous testing in animals for effectiveness and safety before they are ever tested in human subjects or go through the multi-step FDA regulatory process.

Animal Tests Were A Success

A little background on animal testing: Different animal models are created based on the current understanding and development of the disease. These animal models are thoroughly validated before using them in the drug development process.  As such, multiple animal models of depression exists. The most commonly used behavioral models for depression are forced swim test and tail suspension test. These models are based on the hypothesis that when animals are exposed to acute stressors, it leads to behavioral changes akin to depression. Another model commonly used is the neurogenesis model (Neurogenesis is the process by which neurons are formed in the brain).

Reboxetine was tested in these animal models and passed with flying colors. In-fact, reboxetine produced such a robust effect in animal models that it has since been used as a positive control. Newer drugs today are compared and tested against reboxetine in these animal models. It was thought, that it would be a slam-dunk for the treatment of depression. But when it as tested in human studies, it showed little to no effect as an antidepressant.

Why Did Reboxetine Fail in Human Studies?

The failure of reboxetine raises two important questions: “Are the current animal models of depression still valid?” and “Do we have a proper understanding of the disease process and mechanism of depression?” Either one of those questions explains the failure in human studies, but researchers haven’t determined which it is.

So Why is Reboxetine Still Available in Europe?

Good question, and another part of the controversy. The clinical trial results of reboxetine did not publish the negative outcomes of the trial. In other words, Pfizer and Lundbeck, the two companies running the studies, didn’t publish a lot of their data that showed no effect or some of the unfortunate side effects. So, they made the drugs look more effective than they actually were and the side effects seem less pervasive or severe.

What Are The Side Effects of Reboxetine?

The very common side effects (more than one in 10 patients) of reboxetine are:

  • Insomnia
  •  Dizziness
  • Dry mouth
  • Constipation
  • Nausea
  • Sweating

The common side effects (less than one in 10 patients) of reboxetine are:

  • Headache
  • Lack or loss of appetite
  • Agitation, anxiety
  • Paraesthesia (pins and needles), inability to sit or stand still, altered taste sensation
  • Lack of visual focus
  • Increased heart rate, palpitations (heart pounding)
  • Widened blood vessels, fall in blood pressure when standing up, increased blood pressure
  • Vomiting
  • Rash
  • Sensation of incomplete emptying or slowed emptying of the bladder, urinary infection, painful urination, inability to completely empty the bladder
  • Erectile dysfunction (impotence), ejaculatory pain, or ejaculatory delay
  • Chills

The uncommon side effects (between 1 and 10 out of 1000 patients) of reboxetine are:

  •  Dilated pupils
  • Spinning sensation

The rare side effects (between 1 and 10 out of 10000 patients) of reboxetine are:

  • Glaucoma (a condition resulting in increased pressure in the eye)

Are There Any Other Side Effects?

Since reboxetine has been marketed and used, the following side effects have also been reported:

  • Hyponatremia (very low levels of sodium in the blood)
  • Aggressive behavior
  • Hallucinations
  • Suicidal ideation
  • Cold extremities,
  • Allergic skin inflammation
  • Testicular pain
  • Irritability
  • Increased pressure in the eye

Will Reboxetine Ever Be Available In The US?

Probably not. While Pfizer stands behind the drug, and it’s been available in Europe for over two decades, there’s no indication it will come to the US.

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Last Updated: Jan 13, 2020