Gabapentin int he disorder of the impulse control in the Parkinson´s Disease: multicentric study, double-blind, randomized, controlled with placebo.

INTERVENTION: Trade Name: GABAPENTINA KERN PHARMA Pharmaceutical Form: Capsule, hard INN or Proposed INN: GABAPENTINA CAS Number: 60142‐96‐3 Other descriptive name: GABAPENTIN Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 400‐ Pharmaceutical form of the placebo: Capsule, hard Route of administration of the placebo: Oral use CONDITION: PARKINSON´S DISEASE ; MedDRA version: 14.1 Level: PT Classification code 10061536 Term: Parkinson's disease System Organ Class: 10029205 ‐ Nervous system disorders Therapeutic area: Diseases [C] ‐ Nervous System Diseases [C10] PRIMARY OUTCOME: Main Objective: To study the efficay of gabapentin versus placebo in the disorder of impulse control in the Parkinson´s disease, using for its evaluation the Questionnaire for Impulsive‐Compulsive Disorder in Parkinson´s Disease. Primary end point(s): Score in the Questionnaire for Impulsive‐Compulsive Disorders in Parkinson´s Disease‐ Rating Scale. Secondary Objective: 1.To verify if the treatment with gabapentin leads to changes in the Parkinson´s motor state.; 2.To evaluate if gabapentin modifies the anxiety and depression associated to the disorder of impulse control in the Parkinson´s disease.; 3.To analyze if gabapentin has any other effect on the motor aspects related to the Parkinson´s Disease.; 4.To study if the treatment with gabapentin associates to apathy.; 5.To determine the effect of gabapentin versus placebo in the patient´s quality of life.; 6.To verify the security and tolerability of gabapentin, evaluated by the presence of secondary effects.; ; Timepoint(s) of evaluation of this end point: EVERY VISIT SECONDARY OUTCOME: Secondary end point(s): 1. Score in the Unified Parkinson´s Disease Rating Scale, motor section that evaluates the degree of parkinsonism (UPDRS‐III). ; 2. Score in the Unified Parkinson´s Disease Rating Scale, motor complications section, which evaluates motor fluctuations and dischinesia (UPDRS‐IV). ; 3. Score in the PDQ39 (quality of live). ; 4. Score in the Parkinson´s Disease Rating Scale daily life activities section (UPDRS‐II). ; 5. Score in the Starkstein apathy scale and impulsivity in the Barrat scale. ; 6. Score in the Hamilton ansiety and depression scale (HADS). ; 7. Presence of motor symptom detected in the scale of Parkinson´s Disease Nonmotor Symptoms Questionnaire (NMSQ). ; 8. Score in the sleepiness scale of Epworth. ; 9. Incidence of secondary effects in patients treated with gabapentin and placebo. ; Timepoint(s) of evaluation of this end point: EVERY VISIT INCLUSION CRITERIA: 1.Subjects with Parkinson´s disease treated with dopaminergic drugs. 2.Subjects that present disorder of impulse control according to the validated diagnostic criteria (parkinson´s Disease Impulsive‐compulsive Disorders diagnostic interview; Weintraub et al, Mov Disror 2009;30:1461‐7) who after the gradual reduction of the dopaminergic treatment continue presenting disrorder of the impulse control. 3.Older than 18 years old. 4.Signed informed content. 5.Women of childbearing age should get a negative pregnancy test in serum or urine at the screening visit, and accept the use of adequate contraception for at least 14 days before the first dose of study drug to the 14 days after the last. Postmenopause is defined as the absence of menstruation during the year prior to study entry. 6.In men with couples of childbearing age, accept the use of contraceptive methods. Are the trial subjects under 18? no Number of subjects for this ag