Available data suggest that compulsive hoarders have cognitive deficits, particularly with sustaining attention that might contribute their hoarding symptoms.

Compulsive hoarders perform significantly worse than healthy controls on standard attention tasks. These data suggest that the inability to sustain focus may interfere with hoarders' ability to organize, categorize and make decisions about discarding possessions. Stimulants are first-line treatments for ADHD, improve CPT performance in people with ADHD and enhance school performance in children with ADHD. Extended release formulations, such as methylphenidate ER, are associated with better medication compliance. Together, these data suggest that adjunctive methylphenidate ER might be a novel way to improve attention in compulsive hoarders which might improve hoarding symptoms.

The investigators hypothesis is that adjunctive methylphenidate ER will improve attention in compulsive hoarders aged 18-55. The investigators will also explore the safety of methylphenidate ER administration in compulsive hoarders.

Inclusion Criteria:

• Clinically significant compulsive hoarding (Proposed DSM-V criteria) that is principal (i.e. currently most severe and needing of treatment) and has been present for at least one year.
• At least moderate attentional difficulties.
• Able to provide consent.
• Patients can be on or off of serotonin reuptake inhibitors (SRIs) or serotonin and norepinephrine reuptake inhibitors (SNRIs) but dose must be stable for 12 weeks prior to study.

Exclusion Criteria:

• Currently taking any psychotropic medications other than SRIs or SNRIs.
• Presence of psychotic symptoms or lifetime history of schizophrenia, bipolar disorder or other psychotic disorder.
• Current major depression is permitted if clearly secondary in importance to the hoarding.
• Judged clinically to be at risk of suicide (suicidal ideation, severe depression or other factors)
• Any cardiovascular abnormality that increases the risk of participation, including significant history of cardiovascular disease or family history of sudden death.
• Any medical or neurological disorder that increases the risk of participation or that is a medical contraindication for taking methylphenidate (e.g. glaucoma or Tourette's syndrome).
• Current use of any drug that is contraindicated with methylphenidate (e.g. monoamine oxidase inhibitors).
• Female patients who are pregnant or nursing.
• Current or previous treatment with methylphenidate or CBT for hoarding.
• Current ETOH/drug abuse or dependence disorder of dependency in the past 6 months.
• Individuals with mild cognitive impairments, dementia, or significant intellectual deficits.

Individuals with Hoarding Disorder

3 months