PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 28 no. 2 July – december 2013
ORIGINAL ARTICLES

8 PhiliPPine Journal of otolaryngology-head and neck Surgery

ABSTRACT
Objective: To determine whether Psidium guajava leaves mouthwash is effective in the
management of patients with aphthous ulcers.
Methods:
Design: Randomized prospective open label clinical study
Setting: Tertiary Government Training Hospital
Subjects: Thirty two patients diagnosed with aphthous ulcers were randomly divided
into two groups, a treatment group using prepared guava leaves mouthwash, and a control
group using isotonic sodium chloride solution mouthwash given thrice a day for seven days.
Patients were evaluated using a 10-point Visual Analog Scale. The sizes of the aphthous ulcers
were measured using a caliper, and compared on Day 1 and Day 7 for both treatment and control
groups. Results were subjected to statistical analysis using T-test, Mann-Whitney U test and Fisher
Exact test.

Results: Comparison of VAS scores of guava treatment and NSS control groups showed that
there were no differences in pain experienced on Days 1 and 2. However, the VAS scores from Day
3 to 7 had p values ranging from 0.02 - 0.0001 which showed significant differences in resolution
of pain. There was statistically significant marked improvement of pain symptoms as early as
three days post-treatment among patients who were administered guava leaves mouthwash.
Complete resolution of aphthous ulcers in 75% of the study group was observed on Day 7. Mean
ulcer size post-treatment with guava gargle was 0.25mm compared to 0.75mm for NSS gargle.
The mean size difference at day 7 was 1.44mm for the guava treatment group and 0.88mm for the
NSS control group. There was a statistically significant faster resolution of ulcer size on day 7 in
16/16 or 100 % of patients in the treatment group compared with only 10/16 or 62.5% of patients
in the control group. Patients who were administered guava leaves mouthwash generally fared
better than those administered isotonic sodium chloride solution.

Conclusion: Guava leaves mouthwash was effective for aphthous ulcers in terms of reduction
of symptoms of pain and faster reduction of ulcer size. Further clinical trials comparing this
mouthwash against other treatment options are recommended.

Keywords: guava leaves (Psidium guajava), aphthous ulcers, mouthwash

Effectivity of Guava Leaves (Psidium guajava) as
Mouthwash for Patients with Aphthous Ulcers

Ferdinand Z. Guintu, MD
Antonio H. Chua, MD

Department of Otorhinolaryngology
Head and Neck Surgery
Jose R. Reyes Memorial Medical Center

Correspondence: Dr. Ferdinand Z. Guintu
Department of Otorhinolaryngology
Head and Neck Surgery
Jose R. Reyes Memorial Medical Center
San Lazaro Compound, Rizal Avenue
Sta. Cruz, Manila 1003
Philippines
Phone: (632) 743 6921;
(632) 711 9491 local 320 ;
(632) 922 8978070
Email: ferdinandguintu@yahoo.com
Reprints will not be available from the author.

The authors declared that this represents original material that
is not being considered for publication or has not yet been
published or accepted for publication elsewhere, in full or in
part, in print or electronic media; that the manuscript has been
read and approved by all the authors, that the requirements
for authorship have been met by each author, and that each
author believes that the manuscript represents honest work.

Disclosures: The authors signed disclosures that there are no
financial or other (including personal) relationships, intellectual
passion, political or religious beliefs, and institutional affiliations
that might lead to conflict of interest.

Presented at the Philippine Society of Otolaryngology – Head
and Neck Surgery Analytical Research Contest (1st Place),
October 11, 2012, Nathan Hall, GSK Bldg, Chino Roces Avenue,
Makati City, Philippines
Department of Health 1st Research Forum (2nd Place), National
Hospital Week Celebration 2012 on August 9, 2012 at Dr.
Enrique T. Ona Auditorium, Diagnostic Center, National Kidney
and Transplant Institute, East Avenue, Quezon City, Philippines
Annual Residents Research Paper 2012 (3rd Place), Jose R.
Reyes Memorial Medical Center, Rizal Avenue, Sta Cruz, Manila,
Philippines Philipp J Otolaryngol Head Neck Surg 2013; 28 (2): 8-13 c Philippine Society of Otolaryngology – Head and Neck Surgery, Inc.

PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 28 no. 2 July – december 2013

ORIGINAL ARTICLES

PhiliPPine Journal of otolaryngology-head and neck Surgery 9

Herbal medicine is one of the main modalities in traditional as
well as complementary and alternative medicine; and is increasingly
acknowledged due to the extensive use of herbal remedies among
the general population in developed and developing countries
worldwide.1

“Bayabas” or guava (Psidium guajava) is a plant of the family
Myrtaceae.1 In the backyards of most Filipino homes in the rural
countryside, this plant is commonly seen and grown because of its
many uses as fruit and as traditional remedy to treat various ailments.
Research studies have shown that almost all of the parts of this plant
have medicinal qualities, making it one of the most popular therapeutic
plants in the Philippines and one of the approved medicinal plants of
Department of Health.2

Guava (Psidium guajava) is a small tree that can grow up to 3 meters
tall. The fruit, bark and leaves are used as herbal medicine. A decoction
of its leaves is recognized for its effectiveness in curing several ailments,
including the treatment of chronic diarrhea and gastroenteritis. The
most common use of the leaves is for cleaning and disinfecting wounds
by rinsing the afflicted area with a decoction of the leaves. It can also be
used as a wash for uterine and vaginal problems, and is good for ulcers.
Leaf decoction may also be used as mouthwash.2 Psidium guajava has
also been used for the management of various diseases like toothache,
sore throat, and inflamed gums.3

Aphthous ulcers are the most common oral mucosal disorder.4 These
are acute and extremely painful mouth ulcers usually involving non-
keratinized oral mucosal sites. Aphthous ulcers are usually round with
a slightly raised margin and erythematous halo4 and may be classified
into minor, major and herpetiform.5 Approximately 80 percent of
patients have minor aphthous ulcers.5 These are 2 to 8 mm in diameter
affecting nonkeratinized mucosa such as the labial and buccal mucosa
and the floor of mouth or the ventral surface of the tongue. Much less
common are major aphthous ulcers, larger than minor ulcers, often
1 cm or more in diameter. 5 A third and even less common variety is
termed “herpetiform ulceration” and comprises ulcers that are initially
multiple and pinpoint.5 These may interfere with eating, drinking
and swallowing. Several causes have been implicated: local trauma,
viral infection, systemic causes, poor oral hygiene, stress and others.
Although patients have spontaneous healing within 10-14 days, no
specific treatment for aphthous ulcers is yet available.4,6 The goals of
aphthous ulcer treatment have been to control pain and promote
healing.7 Mouthwashes may also help.8

This study was designed to determine whether Psidium guajava
leaves mouthwash is effective in the management of patients with
aphthous ulcers. Specifically, we sought to determine whether Psidium

guajava mouthwash as compared to isotonic saline mouthwash,
decreases the symptoms of pain in patients with aphthous ulcers; and
to assess whether Psidium guajava mouthwash, as compared to isotonic
saline mouthwash, will hasten aphthous ulcer resolution.

METHODS
Study design: Randomized Prospective open label clinical study
Setting: Tertiary government training hospital
Study population: Patients aged 10 years old and above, diagnosed

with minor aphthous ulcers in our hospital outpatient department
from July to December 2011, who were able to understand and give
written informed consent (or assent) and report adverse events were
considered.

Excluded were those with major and herpetiform aphthous
ulcers; those with an oral cavity mass with superimposed ulcer where
malignancy could not be totally ruled out; those with co-morbid
conditions, uncontrolled metabolic conditions or psychiatric conditions;
and pregnant patients.

Thirty-two patients meeting the inclusion and exclusion criteria and
who gave informed consent (or assent, where consent was obtained
from the parent or legal guardian in those < 18 years of age) were
included in the study, fulfilling the pre-determined sample size.

Patient Procedure:
Subjects were divided into a treatment group and control group

using a randomization table. Treatment group patients used the
Psidium guajava leaves mouthwash. They were each given prepared
guava mouthwash solution to gargle and instructed to gargle 250 ml of
the solution for 3 minutes using any watch or clock thrice a day for one
week. Control group patients used isotonic sodium chloride solution
(NSS) mouthwash. They were each given prepared NSS mouthwash
and instructed to gargle 250 ml for 3 minutes using any watch or clock
thrice a day for one week. Patients were asked on Day 7 if there was any
adverse reaction to the gargle.

Treatment and control groups self-accomplished aphthous ulcer
pain scoring daily using a 10-point Visual Analog Scale (VAS) where 0
indicated no symptoms and 10 indicated worst symptoms for the entire
treatment phase, beginning with a baseline in clinic on Day 1. Blank
VAS scales (Figure 1) were given to each participant and collected after
7 days.

Aphthous ulcer sizes for both treatment and control groups were
also measured and recorded using one caliper (Aesculap, Tuttlingen,
Germany) pre- treatment (day 1) and post-treatment (day 7) by a
blinded outpatient resident on duty.

PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 28 no. 2 July – december 2013
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10 PhiliPPine Journal of otolaryngology-head and neck Surgery

Preparation of Materials
Fresh guava leaves were gathered from Pampanga province and

verified by a local biologist. The guava leaves were washed with water,
and batches of 200 gm of guava leaves were boiled in 750 ml of water for
8 to 10 minutes. The boiled leaves were removed and the solution was
cooled and transferred into sealed 1 liter clean clear plastic containers
and placed in the refrigerator. Commercially-available Isotonic Saline
Solution (Euro-med, Cavite) were transferred into sealed clean clear
plastic containers for the control group.

Data management and analysis
Outcome measures were based on comparison of the two groups

after 7 days. Primary outcome measures were reduction in the median
VAS pain score and reduction in the median ulcer size. Summary
measures (mean and percentage) were also determined for the
demographic distribution of study participants and other outcomes.

The null hypotheses tested were as follows:
1. There is no significant difference in VAS scores for pain between

patients using guava mouthwash and patients using isotonic sodium
chloride solution mouthwash.

2. There is no significant difference in size of the aphthous ulcer
between patients using guava mouthwash and patients using isotonic
sodium chloride solution mouthwash.

All data were encoded and tallied in SPSS version 10 for windows
(IBM, New York, USA). Descriptive statistics were generated for all
variables. For nominal data, frequencies and percentages were
computed. For numerical data, mean ± SD were generated. Analysis of
the different variables was done using the T-test, Mann Whitney U test
and Fisher Exact test.

RESULTS
Of a total of 37 patients considered, three patients with uncontrolled

diabetes mellitus and two patients with pulmonary tuberculosis were
excluded. A total of 32 patients were included in this study. There
were 26 females and six males, with ages ranging from 17 to 69 years.
These patients were randomly allocated into two groups of 16 each:
the guava leaves mouthwash treatment group (N=16) and isotonic
sodium chloride solution control group (N=16). All participants
completed the study. No adverse effects were recorded although one
participant in the treatment group complained of nausea attributed to
laryngopharyngeal reflux. There was no significant difference between
the two groups in terms of demographic characteristics of age and sex
with all p values >0.05 (Table 1).

Day 1: Aphthous Ulcer Pain Scoring (Visual analog pain scale)

Day 2: Aphthous Ulcer Pain Scoring (Visual analog pain scale)

Day 3: Aphthous Ulcer Pain Scoring (Visual analog pain scale)

Date:

Patient no.:

1. Circle the number that shows how painful is your aphthous ulcer right now

(Bilugan ang numero na nagpapakita ng gaano kasakit ang iyong singaw ngayon)

No symptom 0 1 2 3 4 5 6 7 8 9 10 very

1. Circle the number that shows how painful is your aphthous ulcer right now

(Bilugan ang numero na nagpapakita ng gaano kasakit ang iyong singaw ngayon)

No symptom 0 1 2 3 4 5 6 7 8 9 10 very

1. Circle the number that shows how painful is your aphthous ulcer right now

(Bilugan ang numero na nagpapakita ng gaano kasakit ang iyong singaw ngayon)

No symptom 0 1 2 3 4 5 6 7 8 9 10 very

Figure 1. Sample blank visual analog scale

Table 1. Comparison of demographic characteristics between the two groups

NSS
(n=16)

Guava
(n=16)

P value

Age in years
Mean ± SD
Sex
Female
Male

44.06 ± 15.24

15 (93.8%)
1 ( 6.2%)

39.40 ± 12.30

11 (68.8%)
5 (31.2%)

0.34 (NS)

0.17 (NS)

There was no significant difference in VAS scores of both groups
on Days 1 and 2 (p = 0.78 and 0.32 respectively). However, there was a
significant difference in VAS scores of both groups from Day 3 until Day
7 (all p values <0.05). The VAS scores of those given guava mouthwash

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PhiliPPine Journal of otolaryngology-head and neck Surgery 11

were significantly lower than those given NSS (Table 2). Comparison
of the differences in VAS scores at different intervals between the two
groups showed that there was a significant difference from Days 3 to 7
(all p values <0.05). The decrease in VAS scores of those given guava was
significantly greater than those given NSS (Table 3). The mean VAS scores

Table 4. Comparison of ulcer size at Days 1 and 7 between the two groups

NSS
(n=16)

Guava
(n=16)

P value

Day 1
1mm
2mm
3mm

Mean ± SD
Day 7
0mm
1mm

Mean ± SD

9 (56.2%)
4 (25.0%)
3 (18.8%)

1.62 ± 0.80

4 (25.0%)
12 (75.0%)

0.75 ± 0.45

6 (37.5%)
9 (56.2%)
1 ( 6.3%)

1.69 ± 0.60

12 (75.0%)
4 (25.0%)

0.25 ± 0.45

0.80 (NS)

0.004 (S)

Table 2. Comparison of VAS Scores at different intervals between the two groups

NSS
(n=16)

Guava
(n=16)

P value

Day 1
Mean ± SD
Day 2
Mean ± SD
Day 3
Mean ± SD
Day 4
Mean ± SD
Day 5
Mean ± SD
Day 6
Mean ± SD
Day 7
Mean ± SD

5.62 ± 1.36

5.44 ± 1.41

4.75 ± 1.00

3.94 ± 1.34

3.18 ± 1.38

3.12 ± 1.36 (3)

2.68 ± 1.14 (3)

5.50 ± 1.26

4.88 ± 1.74

3.62 ± 1.58

2.31 ± 1.74

1.31 ± 1.30

0.38 ± 0.72 (0)

0.31 ± 0.60 (0)

0.78 (NS)

0.32 (NS)

0.02 (S)

0.005 (S)

0.0004 (S)

<0.0001 (S)

Table 3. Comparison of the differences (decrease) in VAS scores at different intervals between
the two groups

NSS
(n=16)

Difference Guava
(n=16)

P value

Day 1 vs Day 2
Mean ± SD
Day 1 vs Day 3
Mean ± SD
Day 1 vs Day 4
Mean ± SD
Day 1 vs Day 5
Mean ± SD
Day 1 vs Day 4
Mean ± SD
Day 1 vs Day 6
Mean ± SD
Day 1 vs Day 7
Mean ± SD

0.18 ± 0.54 (0)

0.88 ± 0.96

1.68 ± 1.44

2.44 ± 1.26

1.68 ± 1.44

2.50 ± 1.03

2.94 ± 1.18

0.62 ± 1.02 (0)

1.88 ± 1.36

3.18 ± 1.94

4.18 ± 1.68

3.18 ± 1.94

5.12 ± 1.31

5.18 ± 1.16

0.17 (NS)

0.02 (S)

0.01 (S)

0.002 (S)

0.01 (S)

<0.00001 (S)

Figure 2. Mean VAS scores at different intervals between the two groups

at different intervals between the two groups are presented graphically
in (Figure 2). There was a statistically significant, marked improvement
of pain symptoms as early as three days post-treatment in the guava
leaves mouthwash group as compared to the isotonic sodium chloride
solution mouthwash group.

The comparison of ulcer sizes between the two groups showed
no significant difference on day 1 (p = 0.80). On the other hand, there
was a significant difference noted in size on day 7 (p = 0.004). The
mean size of ulcers in those given guava mouthwash was significantly
smaller than those given NSS with a mean of 0.25mm and 0.75mm
respectively (Table 4). There was a significant size difference between
the two groups (p = 0.03). The decrease in size of those given guava
mouthwash was significantly greater than those given NSS with a
mean decrease in size of 1.44mm and 0.88mm respectively (Table 5).
The distribution of subjects according to ulcer size at Days 1 and 7 is
presented graphically in (Figure 3). There was a statistically significant,

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12 PhiliPPine Journal of otolaryngology-head and neck Surgery

and morphine were used as standard reference for comparison.10 The
numerous tannins, polyphenolic compounds, flavonoids, ellagic acid,
triterpenoids, guiajaverin, quercetin and other chemical compounds
present in the plant account for the observed anti-inflammatory and
analgesic effects of the plant’s leaf extract.10 Much of the traditional
uses of P. guajava have been validated by scientific research. Toxicity
studies in mice and other animal models as well as controlled human
studies show both leaf and fruit are safe without any side effects.17

The effectivity of guava leaves in pain alleviation may largely be
due to the numerous flavonoids, tannins, polyphenolic compounds,
ellagic acid, triterpenoids, guiajaverin, quercetin and other chemical
compounds present in the plant.10 Flavonoids inhibit biosynthesis of
prostaglandins, which are involved in various immunologic responses
and are the end products of the cyclooxygenase and lipoxygenase
pathways.18 Protein kinases are another class of regulatory enzymes
affected by flavonoids. Inhibition of these enzymes provides the
mechanism by which flavonoids inhibit inflammatory processes.19

Significant decrease in the size of aphthous ulcers may be attributed
to the presence of flavonoids extracted from guava leaves including
morin-3-O-lyxoside, morin-3-O-arabinoside, quercetin and quercetin-
3-O-arabinoside which were reported to have strong antibacterial
and antiviral action.9 Since it is hypothesized that one of the causes of
aphthous ulcer is hypersensitivity and inflammation, the resolution of
size may be due to the effects of flavonoids.

A significant amount of work has been done on the pharmacological
and biological activity and possible application of chemical
compounds. The taste and scent of guava are a limiting factor in proper
standardization of clinical trials as patients could easily recognize
its taste and scent. Hence, VAS was combined with measurement of
aphthous ulcer size to more objectively document its therapeutic
potential.

Our study showed that guava leaves mouthwash, compared to
isotonic saline solution, was effective for aphthous ulcers in terms of
reduction of symptoms of pain and faster reduction of ulcer size. Further
clinical trials comparing this mouthwash against other treatment
options are recommended.

markedly faster resolution of aphthous ulcer size in the guava leaves
mouthwash group as compared to the isotonic sodium chloride
solution mouthwash group.

The results obtained suggest that guava leaves mouthwash is
effective as an alternative treatment for aphthous ulcers.

DISCUSSION
P. guajava has been known to have antimicrobial,9 anti-

inflammatory,10 antitumor,11 antiallergic,12 antihyperglycemic,10,13 and
antimutagenic14 activities. It has been used to treat wounds,15 cough3
and dental diseases.16 Flavonoids extracted from guava leaves including
morin-3-O-lyxoside, morin-3-O-arabinoside, quercetin and quercetin-3-
O-arabinoside were reported to have strong antibacterial action.9 An
in vitro study of aqueous extract of Psidium guajava reduced the cell-
surface hydrophobicity of Strep. sanguinis, Strep. mitis and Actinomyces sp.
responsible in development of dental plaques.16 Psidium guajava also has
been used for the management of various diseases like toothache, sore
throat, inflamed gums, and a number of other conditions.3 Growth of
Staphylococcus aureus and beta-streptococcus group A, as determined
by the disc diffusion method, was inhibited by extract of dry guava
leaves.3 The anti-inflammatory and analgesic properties of the plant’s
leaf extract were determined by using experimental animals. Diclofenac

Table 5. Comparison of ulcer size difference between the two groups

NSS
(n=16)

Guava
(n=16)

P value

Size Difference
0mm
1mm
2mm

Mean ± SD

6 (37.5%)
6 (37.5%)
4 (25.0%)

0.88 ± 0.80

0
9 (56.2%)
7 (43.8%)

1.44 ± 0.51 0.03 (S)

Figure 3. Distribution of subjects according to size at day 1 and day 7 between the 2 groups

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PhiliPPine Journal of otolaryngology-head and neck Surgery 13

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