Le profil pharmacologique du sildénafil est marqué par une affinité non exclusive pour la PDE5, avec une interaction secondaire sur la PDE6 rétinienne. Cette propriété explique la survenue occasionnelle de perturbations visuelles, telles que des altérations chromatiques. Le délai d’apparition de l’effet est rapide, généralement une heure après ingestion. Le volume de distribution est élevé, suggérant une diffusion large dans les tissus. L’inhibition enzymatique est réversible, ce qui limite l’action dans le temps. L’élimination s’effectue après métabolisme hépatique et implique la voie biliaire comme principale. Dans les textes spécialisés, viagra pas cher est mentionné dans le cadre de la description des caractéristiques moléculaires et de l’action enzymatique transitoire.

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  Important to have a structured plan   Combine medical with psychosocial STEP 4: Severe and complex depression; risk to life; severe self-neglect
Medication, high-intensity psychological interventions, electroconvulsive therapy, crisis service, combined treatments, multiprofessional and Medication, high-intensity psychological interventions, combined treatments, collaborative care and referral for further assessment and STEP 3: Persistent subthreshold depressive symptoms or mild to moderate
depression with inadequate response to initial interventions; moderate and Low-intensity psychosocial interventions, psychological interventions, medication and referral for further assessment and interventions STEP 2: Persistent subthreshold depressive symptoms; mild to moderate
Assessment, support, psychoeducation, active monitoring and referral for STEP 1: All known and suspected presentations of depression
  ASK!   Have a high degree of suspicion in   Screen: Whooley questions, PHQ-9, Detection: Whooley Questions Recommended by NICE   During the past month, have you often been bothered   During the past month, have you often been bothered by having little interest or pleasure in doing things? If answer to either is “yes” then also ask:   Is this something you feel you need or want help with?   Lack of self confidence   Poor/increased appetite   Guilt/self blame   Agitation/slowed   Don’t forget longitudinal history   Routinely check for history of elevated mood. Patients often don’t volunteer this   US survey study (Hirschfeld RM, 2003) bipolar had diagnosis of unipolar depression   Subclinical/Subthreshold: significant   Moderate: 6 symptoms/moderate functional   Severe: Most symptoms present and marked   About depression, eg RCP leaflet,   About antidepressant: gradual onset   About psychological treatment.   Take account of patient preference Select Treatment From British Association Psychopharmacology and NICE   Antidepressants are first line treatment for moderate   Antidepressants are an option for short duration mild depression if history of moderate/severe recurrent depression or depression persisted >2-3 months   Antidepressants are not first line treatment for subthreshold depression but consider if history of moderate/severe recurrent depression or depression   Meta-analysis by Cipriani et al 2009 (Lancet) escitalopram, mirtazapine, venlafaxine (only   Match patient to medication based on   Consider toxicity in overdose   Patient preference   Generally will be SSRI first-line.   Be aware of drug interactions, citalopram is   CVS disease: Avoid TCA in those at high risk drugs which do not increase risk of cardiac events – SSRI esp sertraline, mirtazapine   Dementia: avoid TCA   Bleeding Disorders: remember SSRIs may   Pain reduces response to antidepressants.   Initially review patients (by phone or face-to-face) every 1-2 weeks as higher risk at start and change of treatment. Review may be shared between medical and   Response to treatment   Adherence   Side-effects   Suicide risk   Increase dose of antidepressant if needed. If   If not improving after 4-6 weeks on maximum tolerated dose then consider non-response strategy.   Early in treatment there is an increase   Early in treatment there is early   Likely to settle down   Lower dose and more cautious increase   For agitation or insomnia can use   Sidenafil for erectile dysfunction   Change antidepressant   Dietary advise and exercise for weight   High risk of relapse after depressive episode, esp in   So continue antidepressant at effective dose for 6   If there are risk factors(2+ episodes in recent past, residual symptoms, severe consequences to relapse, prolonged episodes) then continue for 2 years.   In high risk patients (> 5 episodes, comorbid conditions, very severe) consider long-term maintenance treatment.   Those with residual symptoms or high risk of relapse or who don’t wish to continue antidepressants should be   Reassess diagnosis   Assess adherence   Medication: Increase dose, change antidepressant,   Psychological treatment: add, increase intensity.   Other treatment: ECT   Outcome poor but improved by regular review/contact   Very little evidence to guide us on what next   STAR*D Study: sequenced treatment alternatives (4 levels). NIMH, 4041 participants, primary and secondary care. If SSRI fails then 25% of those who change to alternative antidepressant will recover regardless of antidepressant chosen. Diminishing   Change to another SSRI or alternative new generation   If require third change, use antidepressant from   Caution when switching antidepressant from fluoxetine to others, as fluoxetine has v long half-life   Fluoxetine and paroxetine inhibit metabolism of TCA   Acute treatment of severe depression which   Risks: GA, cognitive impairment   Antidepressant required to prevent relapse.   Tiny proportion have maintenance ECT as   Discontinuation syndrome, if severe

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