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Efficacy of Acetylcysteine in Patients Undergoing Surgery for Otosclerosis

This study has been completed.
Karolinska Institutet
Information provided by (Responsible Party):
Anders Fridberger, Karolinska University Hospital Identifier:
First received: September 4, 2007
Last updated: September 10, 2013
Last verified: September 2013

In otosclerosis, one of the tiny bones of the middle ear is unable to move normally. Sounds cannot be transferred to the inner ear and a conductive hearing loss ensues. The disorder is usually treated by an operation where the bone is replaced by a prosthesis. This restores hearing at low sound frequencies. At high frequencies, surgery is less effective. The smaller effect at high frequencies is probably caused by surgically induced inner ear damage.

Animal studies have shown that the drug acetylcysteine can protect the inner ear against damage. It is not known whether the drug has similar effects in humans. This study will assess the efficacy of acetylcysteine in patients undergoing surgery for otosclerosis.

Condition Intervention Phase
Otosclerosis Drug: Acetylcysteine Drug: Placebo (NaCl) Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Acetylcystein Vid Stapedotomi

Resource links provided by NLM:

Further study details as provided by Anders Fridberger, Karolinska University Hospital:

Primary Outcome Measures:
  • Hearing thresholds [ Time Frame: one year ]

Enrollment: 152
Study Start Date: September 2007
Study Completion Date: April 2013
Primary Completion Date: April 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1 Drug: Acetylcysteine
150 mg / kg body weight. Drug is dissolved in NaCl to a final volume of 300 mL. This volume is infused starting one hour prior to surgery, and continued 1 hour after the end of surgery.
Placebo Comparator: 2 Drug: Placebo (NaCl)
300 mL 0.9% NaCl


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Otosclerosis where surgery is planned
  • Air / bone gap larger than 20 dB
  • Normal middle ear status

Exclusion Criteria:

  • Hypersensitivity to acetylcysteine
  • Deafness on the other ear
  • Stapedotomy previously performed on the ear
  • Pregnancy
  • Asthma
  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: NCT00525551

Karolinska University Hospital Huddinge
Huddinge, Sweden, SE-141 86
Karolinska University Hospital, Dept. of Otorhinolaryngology
Stockholm, Sweden, SE-171 76
Academic Hospital
Uppsala, Sweden, SE-75185
Sponsors and Collaborators
Karolinska University Hospital
Karolinska Institutet
Study Chair: Dan Bagger-Sjoback, M.D.,Ph.D. Karolinska University Hospital
Principal Investigator: Anders Fridberger, M.D.,Ph.D. Karolinska Institutet
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Anders Fridberger, Dr., Karolinska University Hospital Identifier: NCT00525551     History of Changes
Other Study ID Numbers: KS-OAS1
EudraCT 2006-006243-31
Study First Received: September 4, 2007
Last Updated: September 10, 2013

Additional relevant MeSH terms:
Ear Diseases
Otorhinolaryngologic Diseases
Antiviral Agents
Anti-Infective Agents
Respiratory System Agents
Free Radical Scavengers
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs
Antidotes processed this record on August 17, 2017