Patient Experience with Pyridostigmine

In January 2022, an Illinois-based specialty pharmaceutical company collaborated on a project with Conquer MG to gain insights from MG patients. Conquer MG helped with study review and recruitment, and a study of 102 MG patients was conducted that addressed their use of pyridostigmine (brand name Mestinon®). Pyridostigmine is typically the first drug MG patients are prescribed. With permission from the specialty pharmaceutical company, we share the following data. This information may be shared, but not reprinted. If Conquer MG members have particular interest in this subject and wish to be connected with the company, email and we will make a connection.


Overall, most of the respondents (81%) reported being “somewhat” to “very” satisfied with the effectiveness of pyridostigmine. However, nearly two-thirds (62%) reported some impact with the drug’s side effects, with 43% reporting at least one “severe” side effect (most often diarrhea/constipation at 25%). Many have had to limit their pyridostigmine dose or have found their quality of life diminished due to the medication.

Those who have mild to moderate symptoms are more likely to be satisfied with the drug’s effectiveness and find the side effects acceptable.

About the respondents

  • Nearly all respondents reported their MG sub-type; 85% said they have generalized MG, and 15% reported having ocular MG.
  • All have experience with taking pyridostigmine (77% reported current use).
  • Within the study group, about 80% of the study group describe MG’s daily impact as “mild” or “moderate.” Eleven percent (11%) reported experiencing a hospitalization for MG in the last 12 months.

Pyridostigmine use

As this bar chart shows, 81% of the group use pyridostigmine daily or intermittently. The average daily does is 3x per day. The most typical dose is one tablet (60 mg). Nearly a quarter (23%) limit or have stopped using the medication because of side effects they experience.


Satisfaction with the medicine

Study participants were asked how satisfied they are with the effectiveness of pyridostigmine, and about the side effects they encounter. The following bar charts show:

  • 23% reported dissatisfaction with pyridostigmine side effects.
  • 81% were somewhat to very satisfied with the effectiveness of pyridostigmine
  • 43% of responders reported at least one “severe” side effect (diarrhea/constipation at 25%)
  • 62% reported “some impact” of pyridostigmine side effects
  • About 60% of patients take pyridostigmine with food to minimize side effects
  • Almost half of responders vary pyridostigmine timing based on activities

When asked about the impact of pyridostigmine side effects on daily life, 62% of responders reported some impact. Over one third (35%) reported their activities of daily life (ADL) have been limited, and 30% reported a decrease in quality of life.

Deciding on MG Medications

Side effects are important to MG patients, but so is cost. Among the respondents, 5 out of 6 (83%) chose insurance coverage as an extremely important feature of MG medication. The next most important factors – for 5 of 8 (62% to 65%) – are acceptable side effects, acceptable out-of-pocket costs, and minimal drug interactions.