Albuterol is a drug approved by the US Food and Drug Administration (FDA) for treating breathing problems such as asthma. Studies have shown that albuterol may be beneficial in improving muscle function in people with late-onset Pompe disease. The purpose of this study is to evaluate whether albuterol is safe and effective for improving muscle function in people with late-onset Pompe disease, whether or not they are receiving enzyme replacement therapy (ERT). For this study, albuterol is considered an investigational drug. The word "investigational" means albuterol is not approved by the FDA for individuals with late-onset Pompe disease.

Inclusion Criteria:

1. Diagnosis of Pompe disease by blood acid alpha-glucosidase (GAA) assay and GAA gene sequencing
2. Age: 18+ years at enrollment

Exclusion Criteria:

1. Continuous invasive ventilation (via tracheostomy or endotracheal tube)
2. Clinically relevant illness within two weeks of enrollment including fever > 38.2o C, vomiting more than once in 24 hours, seizure, or other symptom deemed contraindicative to new therapy.
3. Chronic heart disease (Myocardial infarction, arrythmia, cardiomyopathy)
4. History of seizure disorder
5. Hypothyroidism
6. Pregnancy/Breast Feeding [Women of childbearing potential must have a negative urine pregnancy test at each study visit. In addition, at Screening/Baseline women of childbearing potential must have been using a medically acceptable contraceptive for at least 3 months prior to study enrollment OR the subject a) has a regular menstrual cycle, b) Day 1 (onset of menses) for the current cycle is known, and c) the urine pregnancy test can be administered within the first two weeks of the current cycle (between Days 1 and 14)]. The urine pregnancy test will be administered and interpreted by Stephanie Dearmey, Physician Assistant (PA-C), who has completed training from the Department of Obstetrics and Gynecology. Mrs. Dearmey will use a commercially available test kit specified by the point-of-care testing policies. If these criteria for urine pregnancy testing are not met at the Screening/Baseline visit, then a blood pregnancy test will be done.
7. Patients on a non-standard schedule for ERT; for example, weekly infusions as opposed to infusions every two weeks.

The use of the following concommitant meds is prohibited during the study:

• diuretics (water pill);
• digoxin (digitalis, Lanoxin);
• beta-blockers such as atenolol (Tenormin), metoprolol (Lopressor), and propranolol (Inderal);
• tricyclic antidepressants such as amitriptyline (Elavil, Etrafon), doxepin (Sinequan), imipramine (Janimine, Tofranil), and nortriptyline (Pamelor);
• Monoamine oxidase (MAO) inhibitors such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate); or
• other bronchodilators such as levalbuterol (Xopenex), bitolterol (Tornalate), pirbuterol (Maxair), terbutaline (Brethine, Bricanyl), salmeterol (Serevent), isoetherine (Bronkometer), metaproterenol (Alupent, Metaprel), or isoproterenol (Isuprel Mistometer).