BACKGROUND: Musculoskeletal side effects related to isotretinoin are frequently reported. This study aimed to investigate the effect of oral isotretinoin treatment on muscle strength. Our second aim was to evaluate whether there was a correlation between the serum creatine phosphokinase (CPK) level, a specific marker of muscle breakdown, and muscle strength.

METHODS: This study included 30 patients who presented to our hospital and were started on oral isotretinoin treatment for acne vulgaris and 30 patients in the control group who were given local treatment. Age, gender, height and weight of the patients were recorded, and the body mass index (BMI) was calculated. The hamstring and quadriceps muscle strengths of the non-dominant side were evaluated in all patients using an isokinetic dynamometer, and the peak torque (PT) values were recorded. In the isotretinoin group, isokinetic measurements were performed again in those that completed six-month drug treatment and compared with the initial PT values.

BACKGROUND: Musculoskeletal side effects related to isotretinoin are frequently reported. This study aimed to investigate the effect of oral isotretinoin treatment on muscle strength. Our second aim was to evaluate whether there was a correlation between the serum creatine phosphokinase (CPK) level, a specific marker of muscle breakdown, and muscle strength.

METHODS: This study included 30 patients who presented to our hospital and were started on oral isotretinoin treatment for acne vulgaris and 30 patients in the control group who were given local treatment. Age, gender, height and weight of the patients were recorded, and the body mass index (BMI) was calculated. The hamstring and quadriceps muscle strengths of the non-dominant side were evaluated in all patients using an isokinetic dynamometer, and the peak torque (PT) values were recorded. In the isotretinoin group, isokinetic measurements were performed again in those that completed six-month drug treatment and compared with the initial PT values.

Inclusion Criteria:

• being aged 18-45 years
• receiving isotretinoin treatment for the isotretinoin group
• not having used isotretinoin within the last year for the control group

Exclusion Criteria:

• chronic kidney or liver disease,
• uncontrolled hypertension, heart failure,
• malignancy,
• thyroid and bone diseases (e.g., hyperparathyroidism and osteomalacia),
• use of drugs that may affect skeletal metabolism (e.g., corticosteroids, heparin, and anticonvulsants),
• a history of trauma and/or surgery in the lower extremities.
• Patients who discontinued or terminated their isotretinoin treatment were not included in the study.