Group 5's Prescription Drug Webpage

Lyrica (also known as pregabalin) is most often used to treat neuropathic pain; any diseased condition of the nervous system. The drug relieves pain however Lyrica not is cure for the pain.

The most common use of Lyrica is to treat nerve damage caused by diabetes. Diabetic neuropathy is caused when a person has a high blood sugar level over an extended period or time. Diabetic neuropathy damages nerves, especially axons in the feet. The axons of the feet are the longest in the body therefore the most susceptible. Side effects of diabetic neuropathy that is relieved by Lyrica include burning, stabbing sensations, tingling, and numbness. 

Pain caused by shingles (herpes zoster) can be treated with Lyrica. Shingles is caused by the same virus as chicken pox through occur in adults. Blisters similar to chickenpox appear on area or side of the body. In serious cases, the virus can move into the nervous system. Lyrica treats the pain; an anti-viral medication is needed to cure the disease.

Trigeminal nerve pain is a common symptom of neuropathic pain disorders. Pain occurs in the facial area in the form of electric bursts and/or sharp stabbing. The effects of trigeminal pain are erratic and unpredictable causing the affected to fear going out in public. Lyrica is used to relieve the pain, restoring a normal lifestyle. 

Partial onset epileptic seizures are caused by the overexcited nerve cells. The brain releases an overwhelming amount of electrical signals, causing a seizure. Lyrica reduces the extra electrical signals, helping to lessen the effects of the seizure. Seizures are usually not controlled by one medication alone. Lyrica is to be taken with other medication to hope to completely control the seizure.

Pregabalin is a 3-substituted analogue of gamma-amino butyric acid (GABA) and a compound related to Pfizer's hugely successful antiepileptic drug gabapentin. (Source: ABPI)

In hyperactive neurons, more calcium ions enter the cell through calcium ion channels than is normal.  Calcium ions bind to neurotransmitters ready to exit the neuron.  Therefore, the amount of pain neurotransmitters leaving the neuron increases, which increases pain. 

Lyrica increases the amount of the neurotransmitter gamma-aminobutyric acid (GABA), which binds to the alpha-2-delta subunit of the calcium channels in hyperactive neurons, reducing neuronal calcium currents, which are believed to be responsible for effects of neuropathic pain, anxiety, and other pain syndromes.  Lyrica modulates the amount of calcium ions crossing into the neurons due to competitive inhibition.  Since the volume of calcium entering the cell decreases, the amount of pain neurotransmitters leaving the cell decreases as well.  This decreases the level of pain due to the increased release of neurotransmitters.  Testing of the patients taking Lyrica proves that only the calcium channels of hyperactive neurons are affected.  Lyrica does not appear to bind to any other type of ion channel in neurons, so normal cells continue to function properly. 

The side effects of taking Lyrica include dizziness, somnolence, dry mouth, blurred vision, diplopia (double vision), edema, weight gain, asthenia, tremors, and ataxia.  Comparisons between results from placebo and from different doses of Lyrica can range from 5% to 20%. More details on these comparisons can be found in our power point. The most common side effects are dizziness and somnolence, which makes sense considering that Lyrica affects the release of neurotransmitters and the firing of nerve endings.  Usually, the side effects aren’t severe and tend to increase as the dosage of Lyrica increases, becoming the most frequent at the highest dose of 600 mg/day.  None of the side effects associated with the use of Lyrica are permanent, and they usually disappear after a period of time, even with continued usage of the drug.  For most people, the benefits of taking Lyrica out weight the mild or moderate side effects they may experience (6.2% of patients with placebo verses 10% with 150 mg/day or 18.5% with 600 mg/day). Reports of Lyrica causing anxiety and depression also exist, but these effects are not typical.  A majority of people who take Lyrica experience some sort of side effect.

Lyrica does not interact with other drugs commonly used in the treatment of neuropathic pain and epilepsy to a great extent, although it can intensify the neurological affects of oxycodone, lorazepam, and ethanol.  Lyrica is not metabolized, allowing the vast majority of it to be removed from the blood stream and excreted unchanged.  No inhibition of major CYP450 enzymes, which are necessary for the removal of drugs from the blood stream, has been seen with the use of Lyrica.  Weight gain occurred more often in patients taking Lyrica along with thiazolidinedione anti-diabetic drugs.  Overall Lyrica works well as a an add-on drug taken in addition to an established drug regiment.