Evaluating the therapeutic efficacy, tolerability, and safety of an aqueous extract of Costus speciosus rhizome in acute pharyngitis and acute tonsillitis

Methods

The current pilot cohort non-blinded non-controlled trial was conducted at the Otolaryngology-Head and Neck Clinic and Prophet Medicine Clinic, King Abdulaziz University (KAU), Jeddah, Kingdom of Saudi Arabia between May and December 2014. Ethical approval was granted according to the Declaration of Helsinki from the ethical committee of KAU. The primary outcome measure was the remission rate, which was defined as complete absence of all symptoms on day 5. Improvement was defined as any decrease in symptom severity from day one to day 5, excluding remission. The C. speciosus rhizomes used in this study were purchased from a local market in Jeddah, Kingdom of Saudi Arabia. The plant rhizomes were finely ground, and the resultant powder was macerated with deionized water (10% w/v) for 16 hours at room temperature with continuous shaking at 150 rpm in an orbital shaker (Model VS-8480SFN, Vision Scientific, Daejeon, South Korea). The extract was filtered, and the filtrate obtained was lyophilized using a freeze dryer (model FD5512 from ilShin BioBase Co., Ltd, South Korea). Then, a vacuum was used under 5 mm Torr. After the extraction of water from 100 g of the plant rhizome, this yielded 28 g of lyophilized powder. Nasal drops were prepared by suspending the lyophilized extracted powder in distilled water at a concentration of 280 mg/ml. Regarding the selection of concentration, there has been no published study on the use of C. speciosus as a nasal drop. The preparation of the concentration dose was suggested after collecting data from the users of these plants (50 patients).

Patients who fulfilled the following inclusion criteria were included in the study: Male and female patients aged between 3-65 years, with acute pharyngitis or tonsillitis, who agreed to written informed consent; the age of 3 years was selected as members of this age group are at high-risk of group B haemolytic streptococcus, according to the Centor criteria.10 The exclusion criteria were the use of the following agents during the period preceding the study: analgesics <12 hours; antibiotics <24 hours; topical throat pain medication such as echinacea spray or chlorohexidine/lidocaine treatment <4 hours; or systemic corticosteroids within the last month. Serious illness, such as tumors, was also specified as an exclusion criterion. Participation in another clinical trial11 within the previous 30 days was not permitted, and patients who did not present at the follow-up were excluded from the study. One otolaryngologist evaluated the patients clinically. The examination included a detailed history of sore throat, headache, abdominal pain, rhinitis, and cough that were assessed by a Visual Analogue Scale (VAS), and examination for fever, pharyngeal redness and exudate, cervical lymphadenopathy, otitis media, and conjunctivitis. The patients were evaluated by using the Centor score to determine the likelihood of group A beta streptococcus.10 Centor criteria include: fever more than 38°C, absence of cough, tender cervical adenopathy, tonsillar swelling, and age of 3-14 years.

The aqueous solution of C. speciosus was administered as nasal drops at a dose of 0.75 ml (15 drops containing 210 mg extract) for patients aged 2-6 years, and 1.5 ml (30 drops containing 420 mg of the extract) for patients older than 6 years, every 8 hours for 3 days. In the current study, the Costus nasal drop was used at this low dose, as it was mentioned in the literature that the specific dose of nasal administration of other species such as Pelargonium sidoides was 30 drops/3 times per day/7 days in the treatment of acute bronchitis.5 The patients were supplied with 2 degradation bottles of 15 ml, and with daily diaries that contained 6 variables (fever, throat pain, difficulty swallowing, headache, myalgia, and the inability to work) to be scored on a 4-point scale (0: none, 1: mild, 2: moderate, 3: severe). We used the nasal mode of administration as confirmed by Djupesland et al12 that the nasal method has the advantage to overcome the poor bioavailability and slow absorption of systemic drug administration in local rhinosinsitis disease. However, when considering the nasal root, it is important to ensure the protection of the lungs from hazardous exposures of substances through the nose. For this reason, the Costus nasal drops were administered at low doses for shorter durations. Subsequently, the follow-up visit was conducted after one week, during which the patients were evaluated with a full history and examination and for persistent symptoms of acute tonsillitis and pharyngitis by the otolaryngologist. At these follow-up visits, the diaries were collected.

Data were analysed using the Statistical Package for Social Sciences version 16.00 (SPSS Inc., Chicago, IL, USA). Descriptive statistics were computed for all variables. Gender was expressed as a female-to-male ratio. Age was calculated as mean ± standard deviation (SD). Frequency (percent) was calculated on the type of diagnosis and on the improvement and remission rates. The sum of the 6 variants that were scored on 4-point scales was calculated for each of the 15 patients for each of the 5 days. The p-value was set at a value of less than 0.05 with a confidence interval of 95% to determine whether there was a significant difference in the score between each of 2 consecutive days during the duration of the recorded period.