Ototoxic Medications That Cause Tinnitus

تم تعديل 2009/08/31 في علم السموم Toxicology
Ototoxic Medications That Cause Tinnitus

Ototoxic medications
are those that are toxic to the cochlea or vestibular (balance) structures in the ear. These medications have the potential to cause hearing loss, tinnitus and/or dysequilibrium such as dizziness and vertigo.
Ototoxicity came to the forefront of clinical attention with the discovery of streptomycin in 1944. Streptomycin was successfully used in the treatment of tuberculosis; however, a large number of patients were found to develop irreversible cochlear and vestibular dysfunction. Ototoxicity was also shown with the later development of other aminoglycoside antibiotics. Today, many well known pharmaceutical agents have been shown to have toxic effects on the cochleovestibular system. The list includes aminoglycosides and other antibiotics, platinum-based chemotherapy medications, salicylates, quinine and loop diuretics.

The method of action of ototoxic medications differs somewhat among the various drugs. Aminoglycosides seem to potentiate glutamate receptors in the cochlea that promote degeneration of hair cells and cochlear neurons.1 This, in turn, generates a cascade of free radical damage which leads to the destruction of hair cells and neurons

The damage typically begins with the inner row of outer hair cells and progresses through the other rows, then to the inner hair cells. Patients frequently develop symptoms following the cessation of therapy. Ototoxicity-induced hearing loss tends to first manifest in the high frequencies and often causes tinnitus. It then progressively involves the lower frequencies and eventually affects speech recognition.3

Ototoxicity may be reversible or may be permanent, depending on the type of medication used, dosage and duration of treatment. There are many other medications that have been listed as potentially ototoxic.

"1 – Salicylates – Aspirin and aspirin containing products

Toxic effects usually appear after consuming an average of 6-8 pills per day. Toxic effects are almost always reversible once medications are discontinued.

2 –
Non-Steroidal Anti-Inflammatory Drugs (NSAIDS)

– Advil, Aleve, Anaprox, Clinoril, Feldene, Indocin, Lodine, Motrin, Nalfon, Naprosyn, Nuprin, Poradol, Voltarin
Toxic effects usually appear after consuming an average of 6-8 pills per day. Toxic effects are usually reversible once medications are discontinued

[align=left]3 – Antibiotics – Aminoglycosides, Erythromycin, Vancomycin[/align]
a. Aminoglycosides – Streptomycin, Kanamycin, Neomycin, Gantamycin, Tobramysin, Amikacin, Netilmicin. These medications are ototoxic when used intravenously in serious life-threatening situations. The blood levels of these medications are usually monitored to prevent ototoxicity. Topical preparations and eardrops containing Neomycin and Gentamycin have not been demonstrated to be ototoxic in humans.

b. Erythromycin – EES, Eryc, E-mycin, Ilosone, Pediazole and new derivatives of Erythromycin, Biaxin, Zithromax. Erythromycin is usually ototoxic when given intravenously in dosages of 2-4 grams per 24 hours, especially if there is underlying kidney insufficiency. The usual oral dosage of Erythromycin averaging one gram per 24 hours is not ototoxic. There are no significant reports of ototoxicity with the new Erythromycin derivatives since they are given orally and in lower dosages.

c. Vancomycin – Vincocin. This antibiotic is used in a similar manner as the aminoglycosides; when given intravenously in serious life-threatening infections, it is potentially ototoxic. It is usually used in conjunction with the aminoglycosides, which enhances the possibility of ototoxicity

4 – Loop Diuretics – Lasix, Endecrin, Bumex

These medications are usually ototoxic when given intravenously for acute kidney failure or acute hypertension. Rare cases of ototoxicity have been reported when these medications are taken orally in high doses in people with chronic kidney disease.

5 – Chemotherapy Agents – Cisplatin, Nitrogen Mustard, Vincristine

These medications are ototoxic when given for treatment of cancer. Maintaining blood levels of the medications and performing serial audiograms can minimize their toxic effects. The ototoxic effects of these medications are enhanced in patients who are already taking other ototoxic medications such as the aminoglycoside antibiotics or loop diuretics.

6 – Quinine – Aralen, Atabrine (for treatment of malaria), Legatrin, Q-Vel Muscle Relaxant (for treatment of night cramps)

The ototoxic effects of quinine are very similar to aspirin and the toxic effects are usually reversible once medication is discontinued

The signs of ototoxicity, in order of frequency, are

Development of tinnitus in one or both ears.
Intensification of existing tinnitus or the appearance of a new sound.
Fullness or pressure in the ears other than being caused by infection.
Awareness of hearing loss in an unaffected ear or the progression of an existing loss.
Development of vertigo or a spinning sensation usually aggravated by motion which may or may not be accompanied by nauseaT


  • تم تعديل 2009/08/30
    د0 ساره شكرا لك --عمليا لاحظنا أن الجنتامايسين كان يسبب فشل كلوي واضطراب في الشوارد والكرياتينين ولم نلاحظ Ototoxicity
  • dr.joandr.joan عضو ماسي
    تم تعديل 2009/08/30
    على فكرة مقالة رائعة و دقيقة ..بس عندي تساؤل من فترة سمعت إنو نقص التروية الدماغية ممكن يعمل طنين ؟؟؟صحيح؟؟
  • تم تعديل 2009/08/30
  • تم تعديل 2009/08/30
    بصو معروف عن ال aminoglycosides انو اهم اثر جانبى ليها حاجتين مهمين ototoxicity & nephrotoxicity ودول رقم واحد ف اثارهم الجانبيه
    اما اسباب الطنين انا ممكن اكتبلكو عنها بس حد يترجملى يعنى ايه ترويه دماغيه بالانجلش
  • تم تعديل 2009/08/30
    Common causes of tinnitus

    In many people, tinnitus is caused by one of these conditions:

    Age-related hearing loss
    For many people hearing begins to worsen with age, usually starting around age 60. Loss of hearing can cause tinnitus. The medical term for this type of hearing loss is presbycusis.

    Exposure to loud noise
    Loud noises can damage your ability to hear. Heavy equipment, chain saws and firearms are common sources of noise-related hearing loss. Portable music devices, such as MP3 players or iPods, also can cause noise-related hearing loss if played loudly for long periods. While short-term exposure, such as attending a loud concert, usually causes tinnitus that goes away, long-term exposure to loud sound can cause permanent damage.

    Earwax blockage
    Earwax protects your ear canal by trapping dirt and slowing the growth of bacteria. However, when too much earwax accumulates it becomes too hard to wash away naturally (cerumenal impaction), causing tinnitus or problems with hearing.

    Changes in ear bones
    Stiffening of the bones in your middle ear (otosclerosis) may affect your hearing and cause tinnitus. This condition, caused by abnormal bone growth, runs in families.

    Other causes of tinnitus
    Some causes of tinnitus are less common. These include:

    Meniere's disease
    an inner ear disorder. Doctors think it's caused by abnormal inner ear fluid pressure or composition.

    Stress and depression
    This is an especially common diagnosis when hearing tests are normal and no other cause of tinnitus can be identified.

    Head injuries or neck injuries
    These neurological disorders affect nerves or brain function linked to hearing. Head or neck injuries generally cause tinnitus in only one ear.

    Acoustic neuroma
    a noncancerous (benign) tumor. Acoustic neuromas develop on the cranial nerve, which runs from your brain to your inner ear and controls balance and hearing. This condition is also called vestibular schwannoma. It generally causes tinnitus in only one ear.

    Blood vessel disorders linked to tinnitus
    In rare cases, tinnitus is caused by a blood vessel disorder. This type of tinnitus is called pulsatile tinnitus. Causes include:

    Head and neck tumors
    A tumor that presses on blood vessels in your head or neck (vascular neoplasm) can cause tinnitus and other symptoms.
    With age and buildup of cholesterol and other fatty deposits, major blood vessels close to your middle and inner ear lose some of their elasticity — the ability to flex or expand slightly with each heartbeat. That causes blood flow to become more forceful and sometimes more turbulent, making it easier for your ear to detect the beats. You can generally hear this type of tinnitus in both ears.

    High blood pressure
    Hypertension and factors that increase blood pressure, such as stress, alcohol and caffeine, can make tinnitus more noticeable. Repositioning your head usually causes the sound to disappear.

    Turbulent blood flow
    Narrowing or kinking in a neck artery (carotid artery) or vein in your neck (jugular vein) can cause turbulent blood flow, leading to tinnitus.

    Malformation of capillaries
    A condition called arteriovenous malformation (AVM), which occurs in the connections between arteries and veins, can result in tinnitus. This type of tinnitus generally occurs in only one ear.
  • Dr.AhmadDr.Ahmad مدير عام
    تم تعديل 2009/08/30
    شكرا جزيلا دكتورة سارة أكيد معروف أن الــ ototoxicity هي تأثير أساسي للامينوغليكوزيدات

    اما بالنسبة للطنين بصراحة موجز جيد دكتورة و حابب ضيف عن الطنين باللفة العربية :


    [FONT=&quot]معظم الحالات عند الذكور بعمر 50-60 سنة.[/FONT]
    [FONT=&quot]يصنف إلى:- شخصي (المنشأ) يسمعه فقط المريض[/FONT]
    [FONT=&quot] - موضوعي يسمعه الطبيب والفاحص (سماعة)[/FONT]
    [FONT=&quot]أسبابه إما إصابة في:[/FONT]
    [FONT=&quot]1- الجهاز التوصيلي: طنين منخفض التواتر[/FONT]
    [FONT=&quot]2- حسي عصبي: طنين عالي التواتر ما عدا داء منيير يكون منخفض التواتر في المراحل الباكرة[/FONT]
    [FONT=&quot]3- مركزي[/FONT]

    [FONT=&quot]من هذه الأسباب:[/FONT]
    [FONT=&quot]- انسداد بمادة صملاخية: حس ثقل + نقص سمع + طنين [/FONT]
    [FONT=&quot]يبقى الطنين لفترة معينة بعد إزالة المادة الصملاخية حتى يزول.[/FONT]
    [FONT=&quot]- انثقاب غشاء الطبل الرضي.[/FONT]
    [FONT=&quot]- التهاب أذن وسطى حاد.[/FONT]
    [FONT=&quot]- التهاب أذن قيحي مزمن.[/FONT]
    [FONT=&quot]- تصلب الركابة وخاصة إذا ترافق مع تصلب الحلزون.[/FONT]
    [FONT=&quot]- ورم العصب السمعي.[/FONT]
    [FONT=&quot]- داء منيير.[/FONT]
    [FONT=&quot]- بعض الأمراض الداخلية المزمنة (السكري- فقر دم- ارتفاع الضغط) وهنا علاج السبب يشفي الحالة.[/FONT]
    [FONT=&quot]هناك بعض الحالات يكون الطنين غير معروف السبب وهذا ما يسمى الطنين الأساسي علاجه صعب ويزداد في حالة الهدوء (مثلا عند النوم)، والسبب نقص في فعالية القوقعة والعلاج يكون تنبيه القوقعة بأصوات معينة.[/FONT]
    [FONT=&quot]أو قد تكون المشكلة في العصب السمعي- النوى الحلزونية- المراكز الدماغية والقشر الدماغي والطنين يكون مزعج ويسبب عجز.[/FONT]
    [FONT=&quot]ولا يتحسن الطنين حتى بقطع العصب الحلزوني لأن المشكلة قد تكون مركزية- نوى حلزونية وخاصة النواة الزيتونة.[/FONT]

    و بالنسبة لسؤالك حازم : نقص التروية الدماغية Brain Blood Supply Insufficiency لا يسبب طنين tinnitus أبدا و لكن اذا اردنا أخذ المسألة بمنطق فلسفي فنقص التروية الدماغية ممكن يسبب بعد فترة أذية عصبية سواء على مستوى خلايا القشر الدماغي brain cortex في الفص الصدغي temporal lobe أو على مستوى العصب القحفي الثامن Cranial nerve VIII" الدهليزي القوقعي Vestibulocochlear nerve"
  • تم تعديل 2009/08/30
    ثانكس دكتور احمد ع الاضافه
    وكمان اجابه دكتور حازم موجوده بالمقال
    وعنوانه بالون الاحمر
  • تم تعديل 2009/08/31
    التسمم باجنتامايسين يكون تسمم أذني وتسمم الكلى. ونادراً نقص المغنزيوم في الدم بالعلاج المطول، التهاب القولون المرتبط بالصادات، التهاب المعدة، وأيضاً الغثيان والإقياء والطفح واضطرابات الدم.

    تسمم أذني: 1~5% من المرضي الذين يستعملون الدواء أكثر من 5 أيام يمكن أن يحدث لهم تسمم أذن، الذي يميل إلى أن يكون غير رجعي ، يظهر بصورة أساسية كإختلال في وظيفة الدهليز ، ربما يرجع إلى تدمير خلايا الشعيرات بارتفاع مستويات الدواء لفترة طويلة. فقدان السمع يمكن أن يحدث أيضاً.
    تسمم الكلي: يتطلب ، في أقل الحدود ، ضبط الجرعات و يجب أعادة التفكير في ضرورة استعمال الجنتاميسين ، خصوصاً لو كان هناك دواء آخر بديل أقل سميةً. قياس مستويات الجنتاميسين في الدم يكون أساسياً.