Lyrica, generic pregabalin, is a new medication that has anti anxiety, anti-pain and anti-convulsive activity.  Those effects means it has many uses.

In the United States, Lyrica is approved for partial epilepsy, diabetic neuropathy, postherpetic neuralgia and fibromyalgia.  In Europe, it is approved for treating generalized anxiety disorder.

How can it do all that?

On a chemical level, Lyrica is a lot like GABA, which is a neurotransmitter involved in slowing down the activity of certain parts of your brain.  More specifically, Lyrica binds to calcium channels and reduces their intake of calcium.  Doing so lowers the release of other neurotransmitters like norepinephrine and glutamate, which are involved in anxiety and other processes.

This chemical action is very similar to that exhibited by the benzodiazepines, which are known for high addiction and abuse potential.  Because of this similarity, there is the concern that Lyrica can be abused to get high and could possibly be addictive.  It seems that this is possible, but to significantly lesser degree than with the benzodiazepines.

Lyrica has been used by some doctors for off-label uses such as treating arthritis.  While such use may have benefit, it’s important to note that in 2009 a subsidiary of Pfizer plead guilty to marketing inappropriate uses of Lyrica as part of a major settlement.

Dosing:

Lyrica is typically given at from anywhere from 150mg daily to 600mg daily.  Depending on the specific use, the dose may vary.

Use for fibromyalgia

Lyrica was approved in 2007 as a treatment for fibromyalgia, the first medication for that condition.

Patients who take Lyrica for fibromyalgia have reported moderately positive results. On a fibromyalgia pain scale of 1-10, those on it will have roughly a one point reduction in pain compared to those treated with placebo. Roughly 30% of those with Fibromyalgia who use Lyrica will experience a 50% decrease in pain, while only 13% on placebo have such a reduction.

In looking at those numbers, it’s important to remember that, as a condition, fibromyalgia is difficult to treat with very few people reporting significant improvement over time.

Use for diabetic peripheral neuropathy

Lyrica appears to be a solid treatment for diabetic peripheral neuropathy (DPN).  According to an independent analysis by the Cochrane review, 50% of patients with DPN and who take Lyrica report significant reduction in pain over time.

But how does that compare to traditional treatment?

The traditional treatment for DPN is amitriptyline, as recommended by the American Diabetic Association, as well as SSRIs and other medications.  Lyrica seems to have similar effectiveness but may have different side effects.

For DPN, the optimal dose seems to be around 300mg daily, possibly given over two doses.

Lyrica’s Side effects:

20-30% of people who use this medication stop specifically because of a serious side effect, which is somewhat on the high side for a psychiatric medication.  Side effects seem to be dose related with increasing incidence at higher doses.

Most common side effects:

Up to 45% report dizziness

Up to 30% report drowsiness

Up to 20% report ataxia, or issues with smooth movement

Up to 16% report weight gain

Up to 15% report reduced salivation

Up to 10% report constipation

Other possible side effects

Balance issues, euphoric mood, fatigue, pain in the joints, chest pain.

Use of Lyrica may rarely be associated with difficulty paying attention and or concentrating.

There have been reports of tremors associated with this medication and there was a recent case report of an older woman who developed Parkinson’s Disease symptoms most likely due to Lyrica.

This list is not comprehensive; consult manufacturers insert for more.

Drug characteristics

Lyrica is not metabolized by the traditional enzymes in the liver, which means that it may have fewer drug interactions than most drugs.  Roughly 90% of the drug is released in the urine which means both heavy use of kidney and relatively low metabolism by the liver.

This means that kidney impairment may have a significant effect on the medication.

Diet has been shown to alter certain release characteristics of Lyrica but does not seem to effect its efficacy.

Generalized Anxiety Disorder

Generalized Anxiety Disorder (GAD), a disorder characterized by chronic anxiety and worry, is on the surface a bit meaningless. Everyone feels anxious and worries a lot.

What makes GAD abnormal is both the frequency of anxiety, more days than not, its length – over 6 months – and that the anxiety is pretty severe.

There are many models of how GAD works. Here are three particularly useful ones:

Avoidance:

In the avoidance model, anxious thinking is a defensive mechanism. There is a very real problem or potential consequence that could be pretty bad. To avoid thinking about the worst case scenario, sufferers barrage themselves with thoughts to distract from having to deal with “the more emotional topics.”

Treatment: A main strategy for treating the avoidance model of GAD depends on developing the cognitive skills to handle the problems directly. Desensitization, or gradually building tolerance, to the negative thoughts is key.

Another goal is to develop the ability to live in the moment and let things be.

Intolerance of Uncertainty:

In the Intolerance of Uncertainty model, the anxiety develops in response to ambiguous and uncertain situations. Those situations are “stressful and upsetting.” Because problems are over dramatized, normal life upsets can overwhelming.

The worrying becomes self-reinforcing when, anxious about problems, someone doesn’t handle them, which makes it even harder to deal with the next one.

Treatment: Similarly to above, treatment for the intolerance of uncertainty model of GAD focuses on working on internal beliefs that are leading to anxiety. Additionally, problem solving skills should be developed .

Meta-cognitive:

In the meta-cognitive model of GAD, anxiety provoking situations produce thoughts of worry, logically enough. Those initial thoughts, called Type 1 Worry, serve both a protective role as well as partly help deal with the problem by coming up with solutions.

In this model, however, the problem arises when the person starts to worry about their worrying. This Type 2 Worrying leads to excessive self-analysis and self-doubt. While the initial worrying was somewhat based off reality, the second wave is less so.

Treatment: Again, focusing on developing appropriate mental strategies for dealing with stress is a solid model.

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