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Sodium
Enoxaparin
for the Treatment of Tinnitus
By
Barry Keate
Editor's
Note: Last month QT published an article
that discussed new
drug treatments for tinnitus. A QT contributing
author, Charles Smithdeal, MD, directed us to yet
another drug treatment and studies.
Tinnitus
is often caused by hearing impairment which, among
other causes, can be the result of reduced blood circulation
to the inner ear. Micro-thrombosis and/or micro-embolism
can cause this reduced circulation. They both involve
blood clots blocking flow in the affected area. In
the case of thrombosis, the clot is lodged at the
location where it was formed and with embolism, it
was brought to the present location by blood flow.
This
blockage can be the result of inflammation due to
infection or of autoimmune response, such as systemic
lupus, where the body develops an allergic reaction
to its own tissues. There is no widely accepted medical
protocol for the treatment of this condition. The
most commonly used medications are corticosteroids,
vasoactive agents, vitamins and minerals, and anticoagulants.
 Two
clinical trials conducted at the ENT Department at
the University of Genoa in Genoa, Italy have used
sodium enoxaparin (trade name Lovenox) to treat this
blockage. Enoxaparin is a low molecular weight fraction
of the anticoagulant heparin. Due to its low molecular
weight it exerts its effects primarily in the capillaries,
the very small vessels that feed the inner ear. This
medication is also indicated in the treatment of unstable
angina, heart attack, deep vein thrombosis, obesity,
varicose veins and many other conditions.
The
first study 1
was published in 2003. The researchers involved 40
patients between 20 and 65 years old who had experienced
tinnitus and hearing loss of 30 dB involving the medium
frequencies between 2,000 and 4,000 Hz for at least
2 months. The patients were divided into two groups
and admitted to the hospital for 10 days, the duration
of the study. The first group received subcutaneous
enoxaparin twice daily and the second group received
traditional therapy.
On
discharge, all patients treated with enoxaparin experienced
a subjective reduction of symptoms. On a scale of
1 to 4, with 4 denoting incapacitating tinnitus, the
mean value of symptoms fell from 3.8 to 1.5. In the
traditional therapy group the mean value of subjective
tinnitus decreased from 3.7 to 3.1. Objectively, 16
patients (80%) in the enoxaparin group showed improvement
in auditory function. Mean value of hearing improved
for those patients from 19.5 to 23.6 dB across the
2,000 to 4,000 Hz range.
The
second study 2
was published in 2004 and was focused on autoimmune
mediated sensorineural hearing loss, which is characterized
as rapidly progressing hearing loss that has no known
cause.
A
man presented with a 6 month history of progressive
sensorineural hearing loss in the right ear. He made
reference to having systemic lupus erythematosus and
was being treated with the standard medical therapy.
There was no other apparent cause of his hearing loss.
He was affected by a hearing loss of 30 dB in the
range of 2,000 to 4,000 Hz. After treatment with enoxaparin,
he recovered more than 25 dB hearing in the affected
ear.
 Encouraged
by the result, the researchers embarked on a small
study of 8 patients who suffered from unilateral progressive
hearing loss and tinnitus for at least 6 months. The
inclusion criteria were almost the same as the previous
study; 30 dB hearing loss in the 2,000 to 4,000 Hz
range. The exceptional criterion was that all patients
suffered from lupus, which was thought to be the cause
of the hearing loss. The patients were divided into
two groups, an active and a placebo group, and admitted
to the hospital for 10 days.
On
discharge, the active group had a decrease in the
mean score of subjective tinnitus from 3.1 to 1.5
while the placebo group decreased from 3.2 to 2.9.
Hearing improved in 3 (75%) patients in the active
group averaging 17.9 to 22.7 dB across the 2,000 to
4,000 Hz range.
These
two studies were very small and larger studies are
required before definitive results can be finalized.
Nonetheless, the results are very encouraging for
tinnitus patients who have reduced circulation due
to thrombosis or embolism.
It
should be pointed out that all the patients in these
studies had hearing loss and tinnitus in the mid range
(2,000 to 4,000 Hz) and not in higher frequencies.
It is likely they have not suffered from cochlear
hair cell damage, commonly caused by noise exposure
or ototoxicity, which typically results in a high
frequency hearing loss spreading to the lower frequencies
as it progresses.
It
is also important to note that Ginkgo biloba has a
similar effect on micro-thrombosis and micro-embolism.
In one study, 24 patients hospitalized with a form
of dementia due to occluded cerebral arteries were
treated with Ginkgo biloba extract or placebo for
12 weeks. The Ginkgo biloba extract-treated patients
were found to be significantly superior in all measures,
including EEG findings, reaction time and concentration.
Using the venous micro-embolic index (VMI), a measure
of platelet aggregation, the researchers found that
platelet aggregation declined progressively in the
treated patients from a high of 3.6 at baseline to
1.3 at week 12. There was no change in VMI in the
placebo group. 3
Sodium
enoxaparin shows promise for the treatment of tinnitus
caused by micro-thrombosis and micro-embolism. Arches
Tinnitus Relief Formula® contains the highest
quality Ginkgo biloba extract found on the world market
and exhibits many of the same properties and has the
advantage of being non-prescription. These two products
should not be combined except with the approval and
monitoring by the prescribing physician. They are
additive and blood thinning can be excessive, resulting
in bleeding problems.
 Author’s
Note: The research materials for this article
were graciously provided by Charles Smithdeal, MD,
FACS, C.Ht.. Dr. Smithdeal is a board certified Otolaryngologist
and Hypnotherapist and is the Director of the Hypnotherapy
and Tinnitus Institute in St. Petersburg, FL.
He has contributed two prior articles to Quiet
Times that can be seen in our Tinnitus Information
Center, Hypnotherapy
& Tinnitus and Relaxation
Techniques to reduce Tinnitus
References
-
International Tinnitus Journal, Vol. 9, No. 2, 2003.
The Use of Sodium Enoxaparin in the Treatment of
Tinnitus. Mora R, Salami A, Barbieri M, Mora F,
Passal GC, Capobianco S, Magnan J.
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Acta Orolaryngol 2004; Suppl 552: 25-28; Restoration
of Immune-mediated Sensorineural Hearing Loss with
Sodium Enoxaparin: A Case Report. More R, Mora F,
Passali FM, Cordone MP, Crippa B, Barbieri M.
-
Hofferberth B. Simultanerfassung elektrophysiologischer,
psychometrischer und rheologischer Parameter bei
Patienten mit hirnorganischem Psychosyndrom und
erhöhtem Gerfässrisko Ð Eine Placebo-kontrollierte
Doppleblindstudie mit Ginkgo biloba-Extrakt EGB
761. Stodtmeister R, Pillunat L, eds. Mikrozirkulation
in Gehirn und Sinnesor-ganen. Stuttgart: Ferdinand
Enke; 1991:64-74.
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