This site became the new on June 19th. Learn more.
Show more Menu IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu IMPORTANT: Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu
Give us feedback

Evaluation of Optimal Time of Methimazole Discontinuation Before Radio-iodine Therapy in Hyperthyroid Grave's Patients

This study has been completed.
Information provided by (Responsible Party):
S.R.ZAKAVI, Mashhad University of Medical Sciences Identifier:
First received: March 1, 2012
Last updated: March 20, 2012
Last verified: March 2012

Iodine therapy is the best treatment for graves disease.Most patients receive methimozale prior to radio-iodine treatment. This may decrease treatment response to iodine therapy.

Some physicians advice to discontinue methimazole 3 days before radioiodine therapy and others prefer longer off - methimazole period which bothers most patients. This study aimed to evaluate optimum time for methimazole discontinuation in graves disease.

Condition Intervention
Graves Disease Drug: Methimazole

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)
Primary Purpose: Treatment

Resource links provided by NLM:

Further study details as provided by S.R.ZAKAVI, Mashhad University of Medical Sciences:

Primary Outcome Measures:
  • thyroid function tests over one year after radioiodine therapy [ Time Frame: months 1 , 3 ,6,9,12 ]
    thyroid function test may change over one year . In order to consider the patients as cured ,thyroid function tests should reveal hypothyroidism or euthyroidism . In order to rule out temporary hypothyroidism the tests should be repeated after 6 months of radioiodine therapy.

Enrollment: 150
Study Start Date: February 2010
Study Completion Date: January 2012
Primary Completion Date: January 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: group one
This group will be advised to discontinue methimazole 24-48 hour before iodine therapy
Drug: Methimazole
Methimazole was stopped 24-48 before radio-iodine therapy
Active Comparator: group two
methimazole stopped 48-72 hour before radioiodine therapy
Drug: Methimazole
methimazole discontinued 49-72 hours before radioiodine treatment
Active Comparator: group three Drug: Methimazole
methimazole discontinued 73-168 hours before radio-iodine treatment


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • age 18-65
  • graves disease(TSH<0.1 &increased FT4 & positive TSI
  • one or more bartlena criteria for radio-iodine therapy
  • 24 hour RAIU>25%
  • euthyroidism after methimazole treatment

Exclusion Criteria:

  • pregnancy or lactation
  • moderate or severe graves ophthalmopathy
  • CHF or coronary heart disease
  • palpable thyroid nodule
  • lithium or amiodarone or lugol or ipodate treatment
  • recent imaging with contrast agent
  • very large goiter(more than 150 gram)
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01560299

Iran, Islamic Republic of
Mashad University of Medical Sciences
Mashad, Khorasan Razavi, Iran, Islamic Republic of, 91766
Sponsors and Collaborators
Mashhad University of Medical Sciences
Principal Investigator: rasoul zakavi, associate professor Mashhad University of Medical Sciences
  More Information

Responsible Party: S.R.ZAKAVI, associate professor, Mashhad University of Medical Sciences Identifier: NCT01560299     History of Changes
Other Study ID Numbers: Metiodine
Study First Received: March 1, 2012
Last Updated: March 20, 2012

Keywords provided by S.R.ZAKAVI, Mashhad University of Medical Sciences:
graves disease

Additional relevant MeSH terms:
Graves Disease
Orbital Diseases
Eye Diseases
Thyroid Diseases
Endocrine System Diseases
Autoimmune Diseases
Immune System Diseases
Anti-Infective Agents, Local
Anti-Infective Agents
Trace Elements
Growth Substances
Physiological Effects of Drugs processed this record on September 21, 2017