39 - Psychosis

Psychosis

836 The Maudsley® Prescribing Guidelines in Psychiatry CHAPTER 10 Anxiety Anxiety affects many people with MS, with a point prevalence of up to 50%36 and lifetime incidence of 35–37%.37 Elevated rates in comparison with the general ­population are seen for generalised anxiety disorder, panic disorder, obsessive compulsive disorder37 and social anxiety. The uncertainty of prognosis is a major cause of anxiety in MS.38 There are no published trials for the drug treatment of anxiety in MS, but SSRIs can be used and, in non-­responsive cases, venlafaxine might be considered (based on practice in non-­MS patients). Bupropion may also be effective.26 Benzodiazepines may be used for acute and severe anxiety but only for a maximum of 4 weeks and should not be prescribed in the long term. Buspirone and beta-­blockers could also be considered although there is no demonstrated efficacy in MS. Pregabalin is also licensed for anxiety and may be useful in this population group especially where pain relief is required.39,40 People with MS may also respond to cognitive behaviour therapy (CBT). Generally, ­treatment is as for non-­MS anxiety disorders. Pseudobulbar affect Around 25% of individuals with MS experience pathological laughing or crying or other incongruence of affect.41 It is more common in the advanced stages of the disease and is associated with cognitive impairment.37 There have been a few open-­label trials recommending the use of small doses of TCAs such as amitriptyline or SSRIs such as fluoxetine42,43 in MS. Citalopram,44 nortriptyline45 and sertraline46 have been investigated in people with post-­stroke pathological laughing or crying and have shown reasonable efficacy and rapid response. Valproic acid may be effective.47 The combination of ­dextromethorphan and low-­dose quinidine (DMq) is effective.48 Dextromethorphan plus fluoxetine may show similar effects.49 In these combinations, dextromethorphan (an analgesic and cough suppressant) is the active ingredient and quinidine/fluoxetine the metabolic inhibitor. DMq is approved by the US Food and Drug Administration (FDA) as Nuedexta and once held approval in the EU but is not marketed there. Bipolar disorder The lifetime prevalence of bipolar disorder in MS is just less than 10%.50 Lithium can cause diuresis and thus lead to increased difficulties with tolerance in people with MS-­ related bladder disorder. Mania accompanied by psychosis could be treated with low-­ dose antipsychotics such as risperidone, olanzapine51 or ziprasidone.52 Patients requiring psychiatric treatment for steroid-­induced mania with psychosis have been shown to respond to olanzapine.53 Psychosis Psychosis is relatively uncommon compared with other psychiatric disorders.52 A 2015 meta-­analysis estimated the prevalence of psychosis to be 4.3%.1 In a very few cases, psychosis is the presenting complaint of MS.54 There have been few