Adderall XR and Processing Speed in Multiple Sclerosis (MS)

Inclusion Criteria:

• • Males/Females who are ≥ 18 years old and ≤ 59 years old

• Relapsing Remitting, Secondary Progressive or Primary Progressive MS, as per revisedMcDonald's Criteria

• Have not received corticosteroids in last thirty days or a relapse in the last ninetydays

• An Expanded Disability Status Scale (EDSS) of ≤ 6.5

• If female, must neither be pregnant nor breast-feeding

Exclusion Criteria:

• • Have evidence of other medical cause(s) of cognitive impairment

• Have evidence of major depression as determined by a positive Beck DepressionIndex-Fast screen ≥ 13and/or by clinician interview or evidence of severe fatigue witha Fatigue Severity Scale ≥ 5.

• Have demonstrated a hypersensitivity to amphetamines in the past

• Have uncontrolled or labile hypertension (> 135/85 mm Hg, treated or untreated)

• Have a history of structural heart disease, including atherosclerosis or angina

• Have a diagnosis of bipolar disorder or a history of a psychotic episode

• The following medications are not permitted to be used within 14 days the study

1. Monoamine Oxidase Inhibitors

2. Sympathomimetics or methadone

3. Antipsychotic agents

4. Modafinil

• The following medications are permitted if the dose has been stable for ≥ 28 days

1. Short acting benzodiazepines, qhs administration only

2. Anticonvulsants, including gabapentin and pregabalin

3. Bupropion

4. Tricyclic Antidepressants

5. Anti-spasmodics such as baclofen or tizanidine

6. Anticholinergic medication

7. Selective serotonin(-norepinephrine) reuptake inhibitors