Sleep Restriction Therapy + Armodafinil for Insomnia Disorder

30 patients with insomnia will be asked to undergo sleep restriction therapy with armodafinil. This is an open label pilot study to determine if armodafinil is acceptable, tolerated, and ameliorates the side effects of sleep restriction therapy. As part of sleep restriction therapy, participants will be asked to ‘restrict’ their sleep-wake schedules (the minimum time in bed for all participants will be at least five hours). This causes excessive sleepiness, fatigue, & irritability during the initial stages. It is hypothesised that the use of armodafinil will prevent these transient effects of sleep loss. As part of one hour long intervention, participants are instructed to keep a stable bedtime and wake-up time for the length of the treatment (4 weeks). The therapist will devise a "sleep window" that is approved by the participant. The sleep window will be evaluated every week for four weeks via telephone (10 minutes). Time in bed may be modified at weekly intervals by the achievement of 90% sleep efficiency (SE) = Total sleep time / Time in bed * 100) from a one week sleep diary (10 minute session per week via telephone). If 90% SE is achieved on average for any week of the therapy then time in bed is expanded by 15 minutes (either at bedtime or in the morning, depending on the participant). If <85% SE is achieved time in bed is reduced by 15 minutes (but not if it is at the minimum of five hours). If SE = 85-90% Time in bed is held constant. For patients who deem the sleep window too difficult, restrictive, or impossible compromise will be established between the therapist and the patient. Armodafinil (initially 50mg, rising in 50mg amounts to a maximum of 150mg oral dose) once daily (to be taken before 09:00 am) for four weeks during SRT for Insomnia Disorder only. Up titration of armodafinil will take place based on the discretion of the assigned medical practitioner in consultation with the patient. Participants will be prescribed armodafinil by their assigned medical practitioner as part of the first visit to receive sleep restriction therapy. The weekly telephone calls to monitor the effects of sleep restriction therapy will also be used as a method to raise any concerns regarding the use and dose of armodafinil. The assigned medical practitioner will be informed of this and will decide if any action is required. The intervention will end after four weeks of treatment. Adherence to armodafinil will be established with drug tablet return. Adherence to sleep restriction therapy will be evaluated by sleep-wake dairies, actigraphy and a specific weekly sleep restriction therapy adherence scale.