Last reviewed by Editorial Team on August 28th, 2018.
What is Gabapentin prescribed for?
Gabapentin is a Generic name for a drug that with anti-convulsant properties. This drug works by affecting chemicals in the brain that may cause seizures and different types of pain. It is most commonly prescribed for the treatment of epilepsy in patients older than 12 years, and partial seizures in children of ages 3 to 12. It is also prescribed to treat neuropathic pain caused by herpes zoster virus or shingles in adults.
Gabapentin may also be prescribed to treat restless legs syndrome, to prevent hot flashes and to relieve tingling and numbness related to diabetes. It is off-label prescribed for the long-term treatment of migraine and anxiety disorders. Recently, doctors are increasingly prescribed gabapentin to treat pain after surgery as well as a variety of psychiatric disorders, such as chronic anxiety.
Gabapentin is available in following dosage forms: an immediate-release tablet, an extended-release tablet, a capsule, and a solution. It is most commonly used in doses of: 100 mg, 300 mg, 400 mg, 600 mg and 800 mg.
Gabapentin is usually well tolerated in most patients, as it has a fairly mild side-effect profile, and passes unmetabolized through the body. It is also available as brand-name drugs named Horizant, Gralise and Neurontin. FDA approved gabapentin in 1993 under the brand name Neurontin originally manufacturer by Pfizer.
What is Lyrica prescribed for?
Lyrica is a Brand name for a medicine that contains antiepileptic drug pregabalin as an active ingredient which was made as a more potent drug than gabapentin. This drug works by slowing down neural impulses in the brain that may cause seizures. This drug in indicated for following conditions:
· Neuropathic pain, or damaged nerves in the hands, arms fingers, legs, feet, or toes
· Nerve pain caused by shingles, after herpes zoster virus infection
· Fibromyalgia – chronic condition that may cause pain and muscle stiffness
· Pain from nerves damaged by spinal cord injury
· Diabetic peripheral neuropathic pain
· Partial seizure attacks
A study from 2014 published in the New England Journal of Medicine revealed that pregabalin may significantly improve outcomes and may be very efficient as alternative therapy for restless legs syndrome. Lyrica may be also prescribed in combination with other medications to treat certain types of seizures. It is also used off-label for the treatment of anxiety disorders.
Lyrica is available in the form of capsule in following doses: 25 mg, 50 mg, 75 mg, 100 mg, 150 mg, 200 mg, 225 mg and 300 mg. FDA approved pregabalin in 2007. It is originally manufactured by Pfizer with Brand name Lyrica.
What is the difference between Gabapentin and Lyrica in their mechanism of action?
Gabapentin works by interacting with cortical neurons at auxillary subunits of voltage-sensitive calcium channels. Gabapentin increases the amounts of GABA in synaptic spaces, enhances responses to GABA at non-synaptic sites in neuronal tissues, and decreases mono-amine neurotransmitters release.
It mostly acts in the CA1 area of the hippocampus mediated through its binding to presynaptic NMDA receptors. Gabapentin may also affect descending noradrenergic system, and the activation of spinal alpha2-adrenergic receptors. This drugcan also bind and activate the adenosine A1 receptor.
Pregabalin which is the active ingredient of Lyrica works by binding with high affinity to the alpha2-delta site of voltage-gated calcium channels in the brain tissues. Although exact mechanism of action of pregabalin remains unknown, studies suggest that binding to the alpha2-delta subunit could be involved in pregabalin’s antinociceptive and antiseizure effects.
In vitro studies showed that pregabalin can reduce the calcium-dependent release of several neurotransmitters, by modulating the function of calcium channels. Studies also found that pregabalin is also involved in descending noradrenergic and serotonergic signalling.
Although, pregabalin chemically a derivative of gamma-aminobutyric acid (GABA), it does not bind to GABA or benzodiazepine receptors. Opiate receptors, sodium channels and cyclooxygenase enzymes are not involved with the mechanism of pregabalin.
Gabapentin vs Lyrica for neuropathic pain, chronic pain such as migraine and fybromialgia
Recently, pregabalin (Lyrica) was approved by the FDAfor the treatment of post herpetic neuralgia and painful diabetic peripheral neuropathy. Pregabalin has a chemical structure which is very similar to gabapentin. Gabapentin is in comparison a medicine more commonly prescribed to treat seizures but it is now widely used to treat many varieties of neuropathic pain including Complex regional pain syndrome.
Both drugs reduce pain by affecting and reducing overactive pain pathways. Gabapentin has been a great advance in treating Complex regional pain syndrome and neuropathic pain. In addition to its effectiveness, it is also very safe, with no reports of fatal overdose.
In comparison with gabapentin, studies found that Lyrica shows up to a 50 % decrease in pain scores compared to 30 to 40 % reduction in pain scores which were observed after gabapentin use for the same indications. In addition to pain relief, Lyrica also showed improvements in sleep, day-to-day function and mood.
Lyrica also has better elimination half-life time, so it can be dosed on a twice a day compared to gabapentin scheduled of three times a day. At high doses, gabapentin loses on bioavailability, while pregabalin is easily absorbed at all doses. Studies showed that Lyrica begins reducing pain after just one day after it has been started.more faster than gabapentin.
Studies of patients with neuropathic pain who had not responded well to gabapentin and two other medicines shows that pregabalin can provide significant pain relief in those patients.
In addition, Lyrica has been shown to be more effective in treatment of fibromyalgia pain, but also for the pain after spinal cord injury, and anxiety.
Studies also found that almost every patient who was switched to pregabalin therapy from gabapentin prefers pregabalin either because of better efficacy in pain control and fewer side effects. Some patients got pain relief immediately.
The American Academy of Neurology (AAN) found and stated that there is not enough evidence at this time to support the use of gabapentin or Lyrica for the prevention of migraines. However, some clinical trial showed a small benefit after gabapentin use for migraine prevention. But results of some small studies have been shown that in Lyrica is useful in preventing migraines.
Pregablin (Lyrica) vs Gabapentin (Neurontin) high
Since 2004. Gabapentin and Lyrica use was not the subject of reacreational use or abuse, since gabapentin approved indication was only control of seizure attack and Lyrica was not yet approved. When in 2004 gabapentin was granted approval for the treatment of neuropathic pain Gabapentin’s number prescriptions skyrocketed. In 2007 Lyrica was also approved.
During this time, doctors star prescribing these drugs off-label for conditions like drug and alcohol withdrawal, migraine and anxiety disorder. Those were reasons why gabapentin and Lyrica become abused. However gabapentin is more abused than Lyrica because it is longer on the market and it is far cheaper as it is available in generic form.
Because gabapentin causes less side effects compared to benzodiazepines and opioids and also has weaker withdrawal effects, it a very good analgesic and anti-anxiety effects, certain recreational users have gone as far as to suggest that Gabapentin or Neurontin are their new “drug of choice.”
These drugs are also easy to obtain because of theirs widespread off-label use. They are not classified as a “controlled-substance” thus they are available with prescription. These prescriptions can be refilled without an additional doctor visit, electronically – which makes those drugs different than other substances that are subject to strict regulation.
While the “high” associated with Lyrica and gabapentin may not be good, some people really enjoy it. Those who were high on those drugs said that they were filled with relaxation, which makes sense due to muscle relaxant effects of these drugs. Other users claim that the drug makes them feel calm, boosts mood, and even makes them more social which can be linked with anti-anxiety properties of these drugs.
Also these drugs cause minimal side effects if they are not high overdosed. The most common side effects may include: dizziness, drowsiness and lack of coordination. Agitation, restlessness, teeth grinding, or weight gain are less common, which makes it appealing to recreational users. These drugs have also slow onset of action, especially gabapentin.
Typically it is needed about an hour to feel some sort of intoxication which usually lasts several hours. While a slower onset of effect may not be likeable to everyone, the intoxication is said to last several hours.
Gabapentin and Lyrica side effects
|Gabapentin (Neurontin) possible side effects||Lyrica (Pregabalin) possible side effects|
|Ataxia (1-13%)||Dizziness (8-45%)|
|Dizziness (16-20%)||Somnolence (4-36%)|
|Drowsiness (5-21%)||Peripheral edema (16%)|
|Fatigue (11-15%)||Ataxia (1-20%)|
|Somnolence (16-20%)||Fatigue (5-11%)|
|Diplopia (6-10%)||Xerostomia (1-15%)|
|Nystagmus (6-10%)||Weight gain (16%)|
|Tremor (6-10%)||Tremor (11%)|
|Amblyopia (1-5%)||Blurred vision (1-12%)|
|Back pain (1-5%)||Diplopia (12%)|
|Constipation (1-5%)||Asthenia (5%)|
|Depression (1-5%)||Edema (8%)|
|Dry mouth (1-5%)||Facial edema (<3%)|
|Dysarthria (1-5%)||Hypotension (2%)|
|Dyspepsia (1-5%)||Neuropathy (2-9%)|
|Hostility (5-8% children)||Pain (5%)|
|Hyperkinesia (3-5%)||Disorientation (<2%)|
|Increased appetite (1-5%)||Constipation (5%)|
|Leukopenia (1-5%)||Weight gain (4%)|
|Myalgia (1-5%)||Accidental injury (4%)|
|Nervousness (1-5%)||Abnormal thinking (2%)|
|Peripheral edema (1-5%)||Confusion (<7%)|
|Pharyngitis (1-5%)||Amnesia (<6%)|
|Pruritus (1-5%)||Vertigo (1-4%)|
|Rhinitis (1-5%)||Hypoesthesia (2-3%)|
|Vasodilation (1-5%)||Euphoria (2%)|
|Weight gain (1-5%)||Decreased libido (>1%)|
|Abnormal vision (>1%)||Incoordination (2%)|
|Anorexia (>1%)||Vomiting (1-3%)|
|Arthralgia (>1%)||Balance disorder (2-9%)|
|Asthenia (>1%)||Myoclonus (4%)|
|HTN (>1%)||Nasopharyngitis pain (1-3%)|
|Malaise (>1%)||Flu-like syndrome (1-2%)|
Gabapentin and Lyrica Drug Interactions
Are gabapentin (Neurontin) and pregabalin (lyrica) are a death sentence?Can you take neurontin and lyrica together?
Which one is expensive, Gabapentin or Xanax?
According to drugs.com:
× The cost for Gabapentin capsule 100 mg is around $18 for a supply of 90 capsules
× The cost for Gabapentin capsule 300 mg is around $19 for a supply of 90 capsules
× The cost for Gabapentin capsule 400 mg is around $20 for a supply of 90 capsules
× The cost for Gabapentin tablet 600 mg is around $28 for a supply of 90 tablets
× The cost for Gabapentin tablet 800 mg is around $18 for a supply of 90 tablets
× The cost for Lyrica capsule 25 mg is around $352 for a supply of 30 capsules
× The cost for Lyrica capsule 50 mg is around $108 for a supply of 30 capsules
× The cost for Lyrica capsule 75 mg is around $107 for a supply of 30 capsules
× The cost for Lyrica capsule 100 mg is around $206 for a supply of 30 capsules
× The cost for Lyrica capsule 150 mg is around $123 for a supply of 30 capsules
× The cost for Lyrica capsule 200 mg is around $356 for a supply of 30 capsules
× The cost for Lyrica capsule 225 mg is around $555 for a supply of 90 capsules
× The cost for Lyrica capsule 300 mg is around $265 for a supply of 30 capsules
Prices depend on the pharmacy you visit. Prices are for cash paying customers only and are not valid with insurance plans.
Warnings and precautions during Gabapentin and Lyrica use
Gabapentin and Lyrica may increase the risk for suicide. Suicidal behavior and thoughts occurs in about one in 500 people in patients who are taking similar drugs to pregabalin and gabapentin. This risk may begin within a week of starting treatment.
You should let your doctor know if you experience: suicidal thoughts, symptoms of depression, aggression, irritability, panic attacks, extreme worry, restlessness, acting without thinking, judgment impairment, and abnormal excitement. You should also let family and friends to know about these symptoms. If such symptoms, or if a friend or family member thinks you are acting strange, call your doctor right away.
Children at ages of 3 to 12 may experience changes in behavior while taking pregabalin or gabapentin, including: restlessness, poor performance at school, inability to pay attention and angry or aggressive behavior. Children who are younger than 3 years should not be given gabapentin or pregabalin for seizures treatment. Children should also not take gabapentin or pregablin to treat postherpetic neuralgia.
Gabapentin and Lyrica have to be used with caution in elderly patients with kidney disease
Alcohol may interact with gabapentin and pregabalin making side effects more severe and frequent
Never stop gabapentin or Lyrica therapy suddenly because you could experience withdrawal symptoms including sleep disturbance, anxiety, nausea, pain, and sweating.
Doses of gabapentin or Lyrica should be reduced gradually over a period of at least one week and only with your doctor monitoring and advice.
You should tell your doctor if you are taking any prescription pain medications called opioids also known as narcotics. These medicines may increase drowsiness or dizziness if they are taken together with Lyrica or gabapentin.
If you have some kidney disease or you should have any surgery planned including dental or if you have ever had a problem with drug or alcohol abuse let your doctor know before staring therapy with Lyrica or gabapentin.