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REVIEW ARTICLE
The role of caffeine in otorhinolaryngology: guilty as charged?
A. Trinidade
•
T. Robinson
•
J. S. Phillips
Received: 8 May 2013 / Accepted: 23 July 2013 / Published online: 11 August 2013
Ó Springer-Verlag Berlin Heidelberg 2013
Abstract Caffeine is implicated as causing or aggravat-
ing numerous otorhinolaryngological conditions, including
tinnitus, Me
´
nie
`
re’s disease, laryngopharyngeal reflux, glo-
bus pharyngeus and dysphonia. We address caffeine’s
effects in such conditions and to determine whether such
implications are founded. The defined search limits of data
sources included human trials and either randomised con-
trol trials, meta-analyses, editorials, letters, clinical trials,
case reports, comments or journal articles over the last
40 years. MEDLINE, EMBASE and CINAHL databases
were searched using ‘otorhinolaryngological diseases’ and
‘caffeine’ as a duplicate filter. PubMed databases were
searched using ‘caffeine’ in combination with ‘tinnitus’,
‘Me
´
nie
`
re’s’, ‘vertigo’, ‘motion sickness’, ‘imbalance’,
‘vestibular migraine’, ‘voice’, ‘vocal hygiene’, ‘reflux’,
‘ear’, ‘nose’, ‘throat’ and ‘head neck cancer’, respectively.
Searches were not limited to the English language. MED-
LINE, EMBASE and CINAHL database searches identified
417 papers. Of these, 200 abstracts were chosen for further
scrutiny, following which 30 full manuscripts were chosen
for full review. The PubMed database search identified 275
abstracts of which 33 were reviewed. Of the total 692
studies searched, 63 studies were reviewed and 36 were
finally used. At present, there is little evidence in the lit-
erature to support the notion that caffeine causes or
aggravates otorhinolaryngological conditions. In tinnitus,
its withdrawal may actually worsen symptoms whereas in
motion sickness, there is some clinical evidence for its
benefit. More research is needed into the role caffeine plays
in otorhinolaryngological conditions to allow clinicians to
give informed advice to their patients.
Keywords Caffeine Ear Nose Throat
Balance Tinnitus Me
´
nie
`
re’s disease Globus
Dysphonia Voice
Introduction
Widespread caffeine use explains a lot about the twentieth
century—Greg Egan
Caffeine, a crystalline methylxanthine alkaloid stimu-
lant, is the world’s most widely consumed legal, unregu-
lated psychoactive drug [1, 2], due to its ubiquitous
presence in many of the beverages consumed globally,
including coffee, tea, soft drinks, energy drinks and, to a
lesser extent, in chocolate and chocolate-based products.
Its cited effects on health, both positive and negative, are
broad, and range from lowering the risk of Type 2 diabetes
mellitus to inducing psychomotor agitation [3]. The latter
is generally induced at levels of greater than 250 mg/day
(known as caffeinism) and the average adult European
caffeine consumption ranges from 280–490 mg/day, high-
est in Scandanavia [3]. In comparison, the average Amer-
ican coffee drinker consumes approximately three cups of
coffee a day (up to 525 mg/day in brewed coffee) and
represents 54 % of the population.
Within the speciality of otorhinolaryngology, it has been
implicated as the cause or aggravator of several common
ailments, including tinnitus, Me
´
nie
`
re’s disease, laryngo-
pharyngeal reflux and its associated symptoms, and globus
pharyngeus. However, despite such allegations, the evi-
dence to support its status as culprit to these conditions is
conflicting and sparse.
A. Trinidade (&) T. Robinson J. S. Phillips
ENT Department, Norfolk & Norwich University Hospital
NHS Trust, Colney Lane, Norwich NR4 7GJ, UK
e-mail: aarontrinidade@gmail.com
123
Eur Arch Otorhinolaryngol (2014) 271:2097–2102
DOI 10.1007/s00405-013-2648-0
This review considers the role of caffeine in ENT con-
ditions and reviews the available literature to support or
dispel such a role.
Methodology
The defined search limits of this review included human
trials and either randomised control trials, meta-analyses,
editorials, letters, clinical trials, case reports, comments or
journal articles. Additional articles received following
author correspondence were also included. MEDLINE,
EMBASE and CINAHL databases were searched using
both ‘otorhinolaryngological diseases’ and ‘caffeine’ as a
duplicate filter. The PubMed database was searched using
‘caffeine’ in combination with ‘tinnitus’, ‘Me
´
nie
`
re’s’,
‘vertigo’, ‘motion sickness’, ‘imbalance’, ‘voice’, ‘vocal
hygiene’, ‘reflux’, ‘ear’, ‘nose’, ‘throat’ and ‘head neck
cancer’, respectively. Searches were not limited to the
English language.
Results
MEDLINE, EMBASE and CINAHL database searches
identified 417 papers. Of these, 200 abstracts were chosen
for further scrutiny, following which 30 full manuscripts
were chosen for full review based on relevance to the topic
as determined by the authors. The PubMed database search
identified 275 abstracts of which 33 were reviewed, again
based on relevance as determined by the authors. Of the
total 692 studies that our search returned, 63 studies were
reviewed and 36 were finally used for this review. The
decision regarding which papers would be included in the
review was undertaken jointly by AT and JSP.
Table 1 shows the distribution of paper types analysed
either in abstract of full paper form and their levels of
evidence, based on the Oxford Centre for Evidence Based
Medicine classification.
Discussion
Coffee leads men to trifle away their time, scald their
chops, and spend their money, all for a little base, black,
thick, nasty, bitter, stinking nauseous puddle water—The
Women’s Petition Against Coffee, 1674.
Does caffeine really aggravate tinnitus?
It has been long thought that the excessive intake of caf-
feine can aggravate tinnitus, and many patients are given
advice on avoidance of caffeine as well as nicotine, salt,
and a variety of other substances. Medeiros et al. [4] found
that in 744 tinnitus sufferers with otherwise normal hear-
ing, caffeine abuse was found in 45.5 %; however, no basis
for this association was found. In 1988, Slepecky et al. [5]
showed that caffeine causes the shortening of cochlear
outer hair cells (OHCs) through a smooth-muscle like
mechanism (later postulated to be an osmotic process by
Skellett et al. in 1995 [6]) and suggested that this effect
may be responsible for an increase in tinnitus [7]. In a more
recent study by Bobbin, caffeine and ryanodine were used
to prove the role of Ca
2?
release from ryanodine receptors
in the OHCs and supporting cells of organ of Corti on the
function of the cochlear amplifier in guinea pig cochleae
[8]. The results show that caffeine does have a suppressive
effect on the compound action potential of the auditory
nerve and distortion product otoacoustic emissions. How-
ever, whether these described effects of caffeine on the
organ of Corti can themselves cause tinnitus remains
unknown.
Regardless of its effect on the auditory system, recent
research by Claire et al. [9] suggests that caffeine absti-
nence in the management of tinnitus is ineffective and may
indeed aggravate symptoms. In a pseudo-randomized,
double-blinded, placebo-controlled crossover trial of
30 days duration, 66 volunteers with tinnitus and who
usually consumed at least 150 mg/day of caffeine partici-
pated. Volunteers’ usual caffeinated tea/coffee was
replaced with double-blinded supplies under one of two
conditions: either maintenance followed by phased with-
drawal, or phased withdrawal followed by reintroduction
and maintenance. The outcome measure of tinnitus severity
was measured by the total score of the Tinnitus Ques-
tionnaire on Days 1, 15, and 30. Caffeine was found to
have no effect on tinnitus severity (p = 0.97), but signifi-
cant acute effects of caffeine withdrawal were observed,
potentially adding to the burden of the tinnitus [9]. This
latter aspect, however, was not further investigated with
quality of life assessment tools. It is therefore difficult to
draw a definitive conclusion on the effect of caffeine
withdrawal on tinnitus patients.
Overall, whilst there is some evidence of a biological
effect of caffeine on the cochlea, there is no evidence for
presumed association with tinnitus or for its cessation
during tinnitus management.
Caffeine and its role in endolymphatic hydrops
The traditional understanding of Me
´
nie
`
re’s disease is that it
is due to hydrops of the endolymphatic space leading to
rupture of the membranous structures that affect hearing
and balance. However, evolving research has shown that
hydrops is not always associated with Me
´
nie
`
re’s disease
and symptoms may represent a common endpoint of a
2098 Eur Arch Otorhinolaryngol (2014) 271:2097–2102
123
variety of anatomic or physiologic variables, including
ischemic or even autoimmune injuries. Hydrops could be
considered the ultimate cause of such symptoms [10]. It is
this concept of hydrops, however, that is the basis of the
advice given to sufferers of Me
´
nie
`
re’s disease to avoid
alcohol, high salt intake and caffeine. The postulation
underlying this advice is that they cause large fluid shifts
through physiologic fluid compartments and hence result in
inner ear instability [11]. With respect to caffeine, this
would be caused by the sympathomimetic and diuretic
actions of methylxanthine as it distributes into body fluid
compartments [12]. But in a cross-over study by Grandjean
et al. [13], caffeinated drinks were found to have no
significant effects on hydration status when body weight
and urinary output were measured and compared. Simi-
larly, in a recent randomised controlled trial, Ruxton et al.
[14] tested the effect of two different amounts of black tea
(providing 168 and 252 mg of caffeine, respectively)
against a control of boiled water on the physiology of 21
healthy resting, fasted males from the general population.
Interval blood and urine samples were tested over 24 h and
the outcome variables measured included whole blood cell
count, Na
?
,K
?
, bicarbonate, total protein, urea, creatinine
and osmolality for blood; and total volume, colour, Na
?
,
K
?
, creatinine and osmolality for urine. Statistical analysis
revealed no significant differences between tea and water
Table 1 Characteristics of studies used to review the role of caffeine in otorhinolaryngological disorders
Study type Author Location Year published Reference Level of evidence
Review articles Persad South Africa 2012 [2]3a
Wierzejska R Poland 2012 [3]3a
Berlinger USA 2011 [10]3a
Rauch USA 2010 [11]3a
Burgess et al. UK 2010 [15]1a
Estrada et al. USA 2007 [17]3a
Bhavsar UK 2009 [20]3a
Hopkins et al. UK/Denmark 2012 [33]1a
Kaltenbach et al. USA 2006 [34]3a
Galeone et al. Italy 2010 [36]3a
Randomised controlled trial Claire et al. UK 2010 [9]2b
Ruxton et al. UK 2011 [14]2b
Erickson-Levendoski et al. USA 2011 [19]2b
Cohort study
Retrospective Medeiros et al. Brazil 2004 [4]2b
Outcomes research Louis et al. Belgium 2009 [22]2c
Fritz et al. Luxembourg 2009 [23]2c
Case–control study Grandjean et al. USA 2000 [13]3b
Gudjonsson et al. Iceland 1995 [25]3b
Lohsiriwat et al. Thailand 2006 [26]3b
Van Nieuwenhoven et al. Netherlands 2000 [27]3b
Elam et al. USA 2010 [28]3b
Retrospective chart review Block et al. USA 2007 [30]4
Thomas et al. USA 2012 [32]4
Case series Eyeson-Annan et al. Australia 1996 [16]4
Akhtar et al. UK 1999 [18]4
Rouev et al. Bulgaria 2005 [21]4
van Deventer et al. USA 1992 [24]4
Zhou et al. China 2012 [29]4
Cross-sectional survey Cohen et al. USA 2012 [31]4
Laboratory research Slepecky et al. Sweden 1988 [5]5
Skellett et al. USA 1995 [6]5
Ulfendahl et al. Sweden 1987 [7]5
Bobbin USA 2002 [
8]5
Eur Arch Otorhinolaryngol (2014) 271:2097–2102 2099
123
for any of the mean blood or urine measurements. This
contradicts the hypothesis of caffeine causing physiologi-
cal fluid compartment shifts in Me
´
nie
`
re’s disease.
It is also this concept of hydrops that underlies the
administration of diuretics as a medical therapy strategy for
Me
´
nie
`
re’s disease. Diuretics are thought to work by influ-
encing inner ear fluid and electrolyte processing in a sim-
ilar way that it affects ion pumps and ionic gradients in the
kidney [11]. However, a recent systematic review by
Burgess et al. found an insufficient quantity of good evi-
dence to support the effect of diuretics on vertigo, hearing
loss, tinnitus or aural fullness in clearly defined Me
´
nie
`
re’s
disease [15].
In summary, the effect of caffeine on the endolymphatic
system in Me
´
nie
`
re’s disease remains unknown and it seems
unlikely that any effect is related to the direct precipitation
of endolymphatic hydrops.
Caffeine and motion sickness
Motion sickness is considered by some to represent a
mismatch between motion perceived by the visual and
vestibular systems [16]. Sympathomimetic drugs are
known to counteract motion sickness both individually and
in synergistic combination with anticholinergic drugs [17],
and caffeine possesses such an action in the form of
methylxanthine [12]. In a recent double-blinded
randomized controlled trial by Estrada et al. [17], 64 sub-
jects were randomly assigned promethazine 25 mg ? caf-
feine 200 mg, meclizine 25 mg, scopolamine 1.5 mg
transdermal patch or a stimulation wristband, subjected to a
30-min helicopter ride and then another similar ride 7 days
later after having been prescribed a placebo. After filling a
Motion Sickness Questionnaire, the promethazine/caffeine
combination produced the only statistically significant
improvement when compared to the placebo for nausea
(p = 0.019), symptom severity (p = 0.041) and reaction
time (p = 0.05). Given the robustness of the study, this
combination can be recommended for motion sickness.
Caffeine, the larynx and the pharynx
Caffeine is one of the putative causes of poor voice
hygiene, but the evidence for this is lacking. The most
commonly held theory is that the diuretic action of caffeine
leads to dehydration of the vocal fold mucosa. As previ-
ously discussed, there is no evidence that the diuretic
action of caffeine has an effect on hydration or the balance
of body fluid compartments [13, 14].
In 1999, Akthar et al. [18] investigated the more direct,
local effects of caffeine on vocal mucosa in a small pilot
study. Fundamental frequencies, taken as a measure of
disordered voice production, were measured in eight
subjects before and after ingestion of 200 mg of caffeine in
tablet form. Post-ingestion, irregularities of frequencies
during three vocal loading tasks (free speech, reading
passage and singing ‘Happy Birthday’) were analysed. In
all three areas, at least six of the subjects showed sub-
stantial changes in fundamental frequency irregularity
(approximately 8 % for free speech, and 2 % for the other
areas). However, despite this trend, there was considerable
inter-subject variability as evidenced by large standard
deviation values. Other weaknesses of the study include
their use of only one of several voice parameters, namely
fundamental frequency, the lack of subject matching for
age and sex and the absence of a control group. The study
did not, therefore, provide enough statistical support for the
avoidance of caffeine as a valid strategy in improving voice
hygiene. A more recent, robust, prospective, double-blin-
ded, randomized controlled trial by Erickson-Levendoski
et al. [19
] involved randomizing 16 healthy adults to two
sessions where they consumed beverages containing either
caffeine (caffeine concentration of 480 mg) or a sham
(caffeine concentration of 24 mg). Voice measures (pho-
nation threshold pressure and perceived phonatory effort)
were collected. Subjects then completed a vocal loading
challenge and voice measures were again recorded. No
significant differences in voice measures between the caf-
feine and sham conditions were reported (p [ 0.05 in both
parameters).
Other postulations regarding the effect of caffeine on
voice include biochemical interactions between it and the
vocal fold mucosa or possibly a central effect of caffeine
leading to alterations in breathing patterns and bronchial
smooth muscle relaxation indirectly affecting voice [20],
but there remains insufficient evidence for any of these
claims.
Another way in which caffeine is thought to affect the
voice is through its aggravation of laryngopharyngeal
reflux (LPR), a condition which is a direct consequence of
gastro-oesophageal reflux disease (GORD) and which on
its own accord may lead to presentation to the ENT clinic
for a myriad of symptoms, including hoarseness, postnasal
drip, sore throat, dysphagia, chronic cough, globus pha-
ryngeus and chronic throat clearing [21]. Two recent large
epidemiological studies have shown a high incidence of
caffeine ingestion in patients with GORD [22, 23], but the
evidence for the actual effect that caffeine has on the
aggravation on GORD is conflicting. Three recent studies
on the effect of caffeine on the lower oesophageal sphincter
show a relaxation following ingestion of coffee when
compared to a control, despite small numbers in all studies
(12, 12 and 8) [24–26]. Yet in a study by van Nie-
uwenhoven et al. [27] in which 10 healthy subjects
underwent oesophageal motility, gastro-oesophageal
reflux, and intragastric pH measuring via transnasal
2100 Eur Arch Otorhinolaryngol (2014) 271:2097–2102
123
catheterization during exercise, no significant difference
could be found in any of the parameters when subjects
were supplemented with a carbohydrate-electrolyte solu-
tion sports drink with or without 150 mg/L of caffeine or
with water.
With respect to voice, there is evidence that LPR does
have an effect. In a case–control study of 119 patients,
Elam et al. [28] showed that patients with LPR had sig-
nificantly higher mean Voice Handicap Index (VHI) scores
for total, functional and physical domains (p = 0.002, 0.02
and 0.008, respectively). Similarly, in another case–control
study of 196 patients, Zhou et al. [29] showed that in
patients with diagnosed LPR, a significant perturbation of
fundamental frequency and amplitude and a significant
increase in normalization noise energy was present
(p \ 0.01). Similar findings have been found in paediatric
populations [30]. There are authors, however, who support
the notion that dysphonia secondary to LPR is an over-
diagnosed condition due to, amongst other things, the need
for a diagnosis in the absence of pathological findings or
the inability to appreciate the differences in findings on
stroboscopy and laryngoscopy [31, 32]. In addition, whilst
LPR may indeed cause dysphonia, there is no evidence that
initiating anti-reflux treatment is beneficial, as outlined in a
Cochrane review by Hopkins et al. [33].
Whilst there is evidence for the effect of LPR on voice,
the evidence for the effect of caffeine on GORD (and hence
LPR) is conflicting and weak. It can therefore be concluded
that the evidence for caffeine as an aggravator of LPR and
its associated symptoms, including dysphonia, is currently
lacking. Indeed, a systematic review of 2,039 papers by
Kaltenbach et al. [34] supports this statement by conclud-
ing that there is no evidence supporting an improvement in
GORD measures after dietary interventions including the
cessation of tobacco, alcohol or caffeine.
Head and neck cancer: is caffeine a risk factor?
Whilst tobacco and alcohol consumption are well-known
risk factors for the development of head and neck cancers,
other dietary and lifestyle factors, including caffeine-con-
taining beverages such as coffee and tea have also been
implicated [35]. In 1990, when the International Agency
for Research on Cancer evaluated the evidence for the
relationship between coffee intake and head and neck
cancers based on six case–control studies, they found the
evidence to be inadequate [35]. Since then, there have been
over 20 studies further investigating this relationship,
including prospective, case–control and cohort studies, but
all with inconsistent findings. However, an inverse asso-
ciation between coffee intake and the risk of cancer of the
oral cavity and pharynx exists [36]. In one of the most
recent pooled analyses of case-controlled studies of head
and neck cancers, 9 such studies were analysed by Galeone
et al. [36]. They concluded that whilst bias, confounding
factors and reverse causality could not be ruled out, their
results supported the hypothesis that such an inverse
association exists. Coffee ingestion was not found to be
associated with an increased risk of laryngeal cancer. They
stated, however, that as coffee use is so widespread, and
given that head and neck cancer has such a high incidence
and low survival, more research into a causal link between
head and neck cancer and coffee drinking is needed.
Conclusion
Caffeine has been labelled as a perpetrator of a variety of
otorhinolaryngological ailments, but perhaps without much
good evidence. Much of the advice that we prescribe to our
patients seems to be founded in hypotheses that lack sound,
supporting empirical evidence. Though it is tempting to
override such a statement with the claim that ‘‘whilst we do
not know with any certainty that caffeine abstinence can
improve the outlined ailments, what harm could it do?’’
there is evidence that doing so may have a negative effect,
as in the case of tinnitus. More research is needed in all
areas where caffeine is implicated in the ailments pre-
senting to the ENT clinic to allow clinicians to give more
informed advice to their patients.
Conflict of interest None.
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