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Over the years, various medications have undergone evaluation for use in the treatment of fibromyalgia. Those medications include muscle relaxants, corticosteroids, non-steroidal anti-inflammatory medications (NSAIDs), sedatives and tricylic antidepressants.

Tricylic antidepressants actually have some history in the treatment of fibromyalgia. In fact, several of these antidepressants are used in the treatment of the condition. Nortriptyline, doxepin and amitriptyline are all used in the treatment of fibromyalgia. When used for fibromyalgia, in particular, it has been demonstrated in studies to be the most efficient antidepressant for treating the condition.

About amitriptyline for fibromyalgia

Amitriptyline is, as mentioned, a type of tricyclic antidepressant (TCA) used for treating clinical depression. As a result, it’s considered the most common TCA used around the world.

The antidepressant was originally developed by Merck, and was first synthesized in 1960. It was later approved by the Food and Drug Administration in April 1961.

This medication works as an inhibitor of the brain chemicals serotonin and norepinephrine. The medication’s mechanism of action acts strongly on the serotonin transporter, while it causes a moderate effect on the norepinephrine transporter. It doesn’t do anything to affect the dopamine transporter, however.

Amitriptyline is used for several medical conditions, including its FDA approved use for major depressive disorder. That doesn’t stop other medical resources from claiming it plays a role in assisting recovery from other similar conditions.

Amitriptyline is even said to act more efficient than other antidepressants when treating disorders. Interestingly enough, it is actually passed over for other newer antidepressants, since it is known to cause side effects and can get very toxic if consumed to overdose.

Antidepressants and fibromyalgia

Various medications are used to treat symptoms from fibromyalgia. The most common medications include painkillers, sleeping pills and various antidepressants. Antidepressants are said to help treat fibromyalgia symptoms originating from the dysfunction of the brain’s regular functions.

Antidepressants, especially tricylic antidepressants, have been used in the treatment of fibromyalgia for years. Tricylic antidepressants are actually some of the oldest antidepressants on the market, and have been utilized in fibromyalgia treatments for years.

Tricylic antidepressants like amitriptyline work by boosting the levels of the brain’s chemicals or neurotransmitters. When the levels of neurotransmitters are boosted, it prevents the brain from succumbing to impairment in its natural function. These antidepressants mainly boost the neurochemicals serotonin and norepinephrine. After taking these antidepressants, people with chronic pain typically feel much better, since they are known to have lower levels of those aforementioned neurotransmitters present in their brain.

Tricylic antidepressants also play a role in helping relax pain-ridden muscles. It also boosts the body’s natural painkiller, also known as endorphins. Even though these medications have positive results for conditions like fibromyalgia, they have various side effects that might make them hard to take on a regular basis.

Interestingly enough, the tricylic antidepressants that are prescribed for fibromyalgia include duloxetine, milnacipran and venlafaxine. Both duloxetine and milnacipran are already approved by the Food and Drug Administration for fibromyalgia treatment.

Venlafaxine has less research and, therefore, evidence supporting it as an effective treatment. Other antidepressants that have been studied and proposed as potential fibromyalgia treatments include citalopram, paroxetine and fluoxetine.

Amitriptyline falls in the category of relative untested tricylic antidepressants without further support as a fibromyalgia treatment. Though, it hasn’t stopped researchers from studying it and its potential as an effective treatment for fibromyalgia.

Studies on Amitriptyline

Antidepressants have been used to treat chronic pain disorders for years. Even though that’s true, only a limited amount of studies exist covering how tricylic antidepressants help people treat their fibromyalgia symptoms.

According to information collected about fibromyalgia and antidepressants, antidepressants like tricyclic antidepressants ‘produced mild to moderate improvements in [fibromyalgia] symptoms.’ In controlled studies, it was found that as much as ‘one third to half of the monitored patients responded to medication-based treatment.

There was one study that had tested the effects of amitriptyline and fluoxetine on patients with fibromyalgia. Patients in that study were given 25 mg of amitriptyline, while others were given 20 mg of fluoxetine.

As a result, the patients found that either medication helped reduce their fibromyalgia symptoms. Patients who took both medications found that the combination was actually ‘twice as effective’ than just taking one medication alone.

The dosages used for amitriptyline for fibromyalgia are much lower than the usual doses for treating depression. In most cases, dosage can be started at as low as 10 mg each day, taken 2 to 3 hours before going to sleep. This allows the patient to take advantage of the medication’s sedative effects without experiencing those same effects when awake.

Another study of amitriptyline followed 70 different patients with the condition with fibromyalgia. The study’s main purpose evaluated the effectiveness of a regular 50 mg dose for fibromyalgia.

The results of the study revealed some interesting data. The patients who had received the regular 50 mg dose for fibromyalgia saw a ‘significant improvement in their sleep quality, morning stiffness and pain thresholds.’ The ‘tender point score’ taken at the time didn’t improve.

Newer studies concerning the drug for fibromyalgia patients follow the newest iteration of fibromyalgia criteria. A complication of data from other studies about the medication found that ‘amitriptyline for fibromyalgia can continue to be used for [neuropathic pain] treatment, but most patients won’t achieve enough pain relief.’

Various studies collected in the complication lasted as long as 6 weeks (on average). They also tested between anywhere from 15 to as much as 100 participants, with four of the studies hosting over 100 participants. Each study administered doses between 15 mg to 125 mg.

Some studies gradually increased the dose during selected intervals of the study trial. Overall, no concrete evidence was found to support amitriptyline as an effective treatment for fibromyalgia. Some studies did find that it may play a role in reducing some neuropathic pain, such as the pain associated with fibromyalgia.