1. GABAPENTIN AS AN ADDICTION TREATMENT: AN EVIDENCE- BASED STUDY
Dimochristos Papadimitriou, Eleni Geraki, Georgios Nedelkos, Kyriakos Tsantekidis, Maria Mironidou- Tjouveleki
A' Laboratory of Pharmacology, Faculty of Medicine, School of Health Sciences, Aristotle University of Thessaloniki, Greece.
Gabapentin, is a synthetic analogue of the neurotransmitter gamma-aminobutyric acid with anticonvulsant activity
It appears to inhibit excitatory neuron activity. This agent also exhibits analgesic properties
It has high lipid solubility, is not metabolized by the liver, has no protein binding, and doesn't possess the usual drug interactions
It is used to treat partial seizures, amyotrophic lateral sclerosis and painful neuropathies, while it has other potential uses which include monotherapy of refractory partial seizure disorders, treatment of spasticity in multiple sclerosis tremor, mood disorders and attenuation of disruptive behaviors in dementia
Its role in the treatment of various substance addictions is being studied for several years. The objective of this study is to review the efficacy of gabapentin in treating alcohol, cocaine, opioids, nicotine, methamphetamine and cannabis dependence in a clinical level
COCAINE DEPENDANCE- STUDIES
TREATMENT OUTCOME
POS
Raby W.N. et al 2004
Haney M. et al 2005
Hart CL et al 2004
NEG
Reccoppa L. et al 2004
Berger S.P. et al 2005
Bisaga A. et al 2006
Hart C.L. et al 2007 (a)
Hart C.L. et al 2007 (b)
Gonzalez G. et al
2007
Mancino J.M. et al 2014
COCAINE
Gabapentin has been used in several clinical studies as a monotherapy or a combination treatment against cocaine addiction with disappointing results, despite earlier indications
It had no effect on craving or abstinence rates, thus did not affect the substance usage
Did not decrease the subjective effects of cocaine usage
Combined with sertraline negatively affected sertraline’s results
OPIOID DEPENDANCE- STUDIES
TREATMENT OUTCOME
 POS
Berger A. et al 2003
Kumar P. et al 2003
Freye E, et al 2004
Kheirabadi G.R. et al 2008
Salehi M. et al 2011
Sanders C.N. et al 2013
Moghadam S.M et al 2013
NEG
OPIOIDS
Gabapentin was tested against opioid addiction with positive results as a monotherapy or a combination treatment
It reduces the usage and alleviates opioid withdrawal symptoms
Decreased the feeling of pain and cold , yawning, diarrhea, dysphoria and muscle tension
The effects of gabapentin seems to be dose-related
ALCOHOL
Gabapentin has been used in several clinical studies as a monotherapy or a combination treatment against alcohol addiction with promising results
It prolongs the abstinence period, therefore reducing the risk of relapse due to the fact that it alleviates withdrawal symptoms
Reduces insomnia and mood instability
In combination with flumazenil or naltrexone a better treatment outcome was observed
The effects of gabapentin appears to be dose-related
ALCOHOL DEPENDANCE- STUDIES
TREATMENT OUTCOME
POS
Karam-Hage et al 2003
Voris J. et al 2003
Bazil C.W. et al 2005
Mariani J.J. et al 2006
Furieri F.A. et al 2007
Malcolm R. et al 2007
Brower K.J. et al 2008
Mason B.J. et al 2009
Hugh Myrick et al 2009
Raymond F. Anton et al 2009
Mehrdal Salehi et al 2011
Raymond F. Anton et al 2011
Joseph P. Schacht
et al 2011
Joseph P. Schacht et al 2013
Christopher J. Stock et al 2013
Barbara J. Mason et al 2014
NEG
Bonnet U. et al 2003
Bisaga A. et al 2006
Myrick H. et al 2007
CANNABIS DEPENDANCE- STUDIES
TREATMENT OUTCOME
POS
Mason B.J. et al 2012
NEG
METHAMPHETAMINE
DEPENDANCE- STUDIES
TREATMENT OUTCOME
POS
Urschel H.C. et al 2007
NEG
Ling W. et al 2012
NICOTINE DEPENDANCE- STUDIES
TREATMENT OUTCOME
POS
Sood A. et al 2007
NEG
White W.D. et al 2005
Sood A. et al
2010
CANNABIS-METHAMPHETAMINE- NICOTINE
Gabapentin significantly decreased withdrawal symptoms such as craving, sleep and mood disorders concerning cannabis dependence
Was assessed twice combined with flumazenil and hydroxyzine against methamphetamine dependence . One research suggested that there was a substantial reduction in both usage and craving of methamphetamine while the other suggested that gabapentin was ineffective
Regarding addiction to nicotine there were three studies with opposing results. One study suggested that gabapentin decreased the number of cigarettes per day and the abstinence rate but the other two studies suggested that gabapentin had no effect on smoking cessation and nicotine dependence.
CONCLUSIONS
Gabapentin was well tolerated with minor side effects even in the highest doses (3200 mg- cocaine addiction treatment)
It holds promise as an effective treatment for alcohol and opioids addiction as a combination therapy or monotherapy, but it had no effect on cocaine dependence
The effects appear to be dose- related
Regarding cannabis, methamphetamine and nicotine dependence further research needs to be conducted due to the existence of little evidence