What could be causing high-pitch tinnitus in a patient taking a lower dose of clonazepam (Klonopin)?

Clonazepam Withdrawal as a Cause of High-Pitch Tinnitus

The high-pitch ringing (tinnitus) experienced by a patient who has been on a lower dose of clonazepam for weeks is most likely due to benzodiazepine withdrawal, which can cause tinnitus as a withdrawal symptom.

Understanding Clonazepam and Tinnitus Relationship

• Clonazepam is a long-acting benzodiazepine with an elimination half-life of 30-40 hours that is rapidly absorbed after oral administration, with a bioavailability of 90% 1
• Failure to take clonazepam or dose reduction has resulted in immediate relapse of symptoms, with rapid control restored after resumption of treatment 1
• Benzodiazepines like clonazepam have been used to treat tinnitus through their action on GABA-benzodiazepine-chloride receptors 2
• Clonazepam has shown effectiveness in treating tinnitus in controlled studies, with significant improvement in tinnitus loudness (74% of subjects), duration (63%), and annoyance (79%) 3

Mechanisms of Withdrawal-Induced Tinnitus

• Clonazepam works on GABA receptors in the brain, and withdrawal can lead to neurochemical imbalances affecting auditory processing 2
• When a patient reduces their clonazepam dose, the GABA-benzodiazepine-chloride receptor function may be disrupted, potentially causing tinnitus 2
• Studies have shown that patients with predominantly central type tinnitus experience significant tinnitus control with medication directed to the GABA-benzodiazepine-chloride receptor 2
• Withdrawal from benzodiazepines can cause same-night relapse of symptoms, including tinnitus 1

Other Potential Causes to Consider

• Tinnitus is a symptom defined by the perception of sound in the absence of external stimuli, affecting more than 50 million Americans 1
• Patients describe tinnitus as various sounds ranging from hissing, buzzing, ringing, pulsations, and clicking to a roaring kind of noise 1
• Primary tinnitus is idiopathic, whereas secondary tinnitus is associated with an underlying cause 1, 4
• Subjective tinnitus is perceived by the patient only and comprises 70% to 80% of cases 1, 4
• Sensorineural hearing loss is the most common underlying cause of tinnitus 4
• Medication-induced tinnitus is a known phenomenon with over 130 drugs reported to be potentially ototoxic 5

Clinical Approach to Clonazepam-Related Tinnitus

• Determine if the tinnitus began specifically after the dose reduction of clonazepam 1
• Assess if the tinnitus is pulsatile or non-pulsatile, as this helps determine the underlying cause 1
• For non-pulsatile tinnitus without focal neurological abnormalities or asymmetric hearing loss, imaging studies are generally not recommended 1
• If the tinnitus is unilateral or asymmetric, or associated with hearing loss, a comprehensive audiological examination is recommended 1

Management Options

• If withdrawal is suspected as the cause, consider stabilizing the clonazepam dose, as studies have shown that failure to take clonazepam results in same-night relapse of symptoms 1
• For patients experiencing withdrawal symptoms, a gradual tapering schedule is preferred over abrupt discontinuation 1
• Consider that many patients are unable to substantially reduce their dose despite periodic attempts at gradual tapering without experiencing prompt reemergence of symptoms 1
• If the patient cannot tolerate clonazepam or needs to discontinue it, alternative treatments such as melatonin may be considered, as it has fewer side effects 1

Monitoring and Follow-up

• Monitor for other withdrawal symptoms such as anxiety, insomnia, and irritability 1
• Be aware that clonazepam side effects can include sedation, impotence, early morning motor incoordination, confusion, and memory dysfunction 1
• Recognize that clonazepam at 0.5 to 1.0 mg can be associated with the possible risk of developing or worsening sleep apnea 1
• If the tinnitus persists despite addressing the withdrawal, consider other etiologies and appropriate evaluations 1