Cinnamon-Enhanced Topical Roll-On: A Sustainable Solution for Dysmenorrhoea and Chronic Inflammation

Dysmenorrhoea, or menstrual pain, is a prevalent condition among menstruating individuals, often resulting in significant discomfort and a reduced quality of life. The standard medical approach typically involves non-steroidal anti-inflammatory drugs (NSAIDs), which, although effective, may cause unwanted effects with prolonged use. Chronic inflammation, a key player in many long-term illnesses, similarly demands therapeutic strategies that are both effective and safe. In response, the medical community has increasingly turned its attention to plant-based and alternative remedies, seeking out natural therapies with fewer side effects.^[1] NSAIDs and hormonal contraceptives remain the cornerstone treatments for primary Dysmenorrhoea. Despite their effectiveness in managing pain, these interventions frequently cause gastrointestinal irritation and other adverse reactions. Moreover, not all patients achieve relief from conventional therapy, prompting the exploration of alternative treatments. Similarly, in chronic inflammatory diseases, the reliance on conventional drugs can lead to complications, making safer therapeutic alternatives highly desirable.^[2] NSAIDs are typically the first line of treatment for Dysmenorrhoea, but their usage is often associated with side effects such as dizziness, dyspepsia, headaches,^[3] nausea, allergic reactions, mood alterations, bleeding tendencies, metabolic imbalances, and even severe outcomes like malignancy or death in rare cases.^[4] Hormonal therapies, such as oral contraceptives, are also used as a secondary or alternative intervention. These agents reduce prostaglandin levels and alleviate menstrual pain, but can also cause side effects like irregular bleeding, headaches, nausea, mood shifts, and weight fluctuations, which often result in poor compliance among users^[5,6]. Herbal remedies have long been utilized across civilizations for treating various ailments, and cinnamon—sourced from the bark of trees in the Cinnamomum genus is a prime example of such a plant. Known for its culinary applications, cinnamon also offers medicinal benefits due to its antioxidant, antimicrobial, and anti-inflammatory actions. Its potential role in alleviating menstrual pain and related symptoms has been increasingly validated through scientific studies^[7]. Topical formulations present a promising delivery method, allowing active ingredients to act directly on affected areas, minimizing systemic exposure and associated risks. Among these, roll-on products are especially favored for their convenience, targeted application, and portability. A roll-on using cinnamon oil could combine these benefits with the therapeutic properties of cinnamon, offering a new and practical approach to treating Dysmenorrhoea and localized inflammation.

1. Objective of the Study

This research focuses on formulating and evaluating a cinnamon-based roll-on intended to address Dysmenorrhoea, inflammation, and other associated conditions. The specific goal is to develop a stable and effective roll-on product capable of delivering localized relief with minimal side effects.

2. Mechanism of Action

Primary dysmenorrhoea refers to menstrual pain that occurs in the absence of identifiable pelvic pathology and affects up to 90% of menstruating individuals, particularly adolescents and young women.^[8] The pathophysiology primarily involves elevated production of uterine prostaglandins, especially prostaglandin F2α (PGF?α) and prostaglandin E2 (PGE?), which stimulate excessive uterine contractility, vasoconstriction, and localized ischemia culminating in pain and discomfort.^[9] Cinnamon, derived from Cinnamomum zeylanicum and Cinnamomum cassia, has been traditionally employed in the management of gynecological conditions. Recent scientific evidence supports its therapeutic potential in primary dysmenorrhoea owing to its analgesic, anti-inflammatory, antioxidant, and smooth muscle-relaxant properties.^[10]

• Inhibition of Prostaglandin Synthesis

Cinnamon exerts a critical pharmacological effect by modulating the prostaglandin synthesis pathway. Bioactive constituents such as cinnamaldehyde, cinnamic acid, and eugenol demonstrate selective inhibition of cyclooxygenase-2 (COX-2), thereby attenuating the biosynthesis of PGF?α and PGE?.^[11,12] Experimental models have confirmed that cinnamaldehyde significantly suppresses COX-2 gene expression, resulting in reduced prostaglandin levels and subsequent inflammation.^[13] This mechanism mirrors the action of non-steroidal anti-inflammatory drugs (NSAIDs) but with potentially fewer adverse gastrointestinal effects.^[14]

• Anti-inflammatory and Antioxidant Activities

Cinnamon is a rich source of polyphenolic compounds that downregulate key pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), which are closely linked to endometrial inflammation during menstruation.^[15,16] The anti-inflammatory action helps alleviate pain by mitigating cytokine-induced uterine irritation. ^[17] Moreover, its antioxidant constituents such as flavonoids and tannins neutralize reactive oxygen species (ROS), thereby reducing oxidative stress in endometrial tissue, a condition known to amplify inflammatory responses and worsen dysmenorrhoeic symptoms.^[18,19]

• Regulation of Calcium Channels and Uterine Smooth Muscle Relaxation

Uterine smooth muscle contractility is mediated by intracellular calcium (Ca²?) influx. Cinnamon has been shown to inhibit voltage-gated calcium channels, thereby decreasing intracellular calcium concentrations and reducing the intensity of uterine contractions.^[20]Furthermore, it suppresses the activity of myosin light chain kinase (MLCK), a Ca²?-dependent enzyme that facilitates myometrial contraction, promoting uterine relaxation and pain relief .^[21]

• Neuroendocrine Modulation and Central Analgesic Effects

Emerging evidence suggests that cinnamon may also influence central mechanisms of pain perception. It has been reported to increase β-endorphin levels—endogenous opioids that bind to μ-opioid receptors, diminishing nociceptive transmission and promoting analgesia. Additionally, cinnamon may modulate neurotransmitters such as serotonin and dopamine, which play essential roles in regulating mood, stress response, and menstrual-related pain. ^[32]

PLANT PROFILE

• Taxonomy and Nomenclature

Cinnamon is an aromatic spice derived from the inner bark of trees classified under the genus Cinnamomum, which belongs to the Lauraceae family. Among the most commonly used species for spice production are Cinnamomum verum (also known as true or Ceylon cinnamon) and Cinnamomum cassia (commonly referred to as cassia or Chinese cinnamon). Other significant species include Cinnamomum burmannii (Indonesian cinnamon) and Cinnamomum loureiroi (Vietnamese or Saigon cinnamon).

• Morphological Characteristics

Cinnamon is a perennial evergreen tree or shrub classified under the Lauraceae family. In natural settings, it can attain a height ranging from 10 to 15 meters, although cultivated specimens are typically pruned to shorter sizes to facilitate easier harvesting. It possesses a robust taproot system that provides structural support and stability. The trunk is upright, cylindrical, and woody, often exhibiting dense branching. Commercial interest centers around the bark—while the outer bark is coarse and greyish-brown in appearance, the inner bark is smooth, thin, aromatic, and light brown in color.

• Phytochemical Composition

The characteristic scent and flavor of cinnamon are primarily due to its essential oil content, with cinnamaldehyde serving as the dominant constituent—comprising approximately 60% to 90% of the oil, depending on the species.

• Therapeutic Applications

Cinnamon has been extensively studied for its medicinal potential in the management of primary dysmenorrhoea. Cinnamon demonstrates strong antioxidant properties by neutralizing free radicals and mitigating oxidative stress, which contributes to uterine inflammation. Multiple studies have confirmed its anti-inflammatory effects, particularly through its essential oils. Flavonoid compounds such as gossypin, gnaphalin, hesperidin, hibifolin, hypolaetin, oroxindin, and quercetin—isolated from cinnamon—are known to possess significant anti-inflammatory activity. These actions help in reducing uterine inflammation, easing menstrual discomfort, and improving overall menstrual health.

Table no.1: Physical and chemical properties of cinnamon

Table no. 2: Pharmacokinetic profile

Table no.3: Pharmacodynamics Profile

MATERIALS AND METHODS

Table no. 4 : Formulation table

RESULT AND DISCUSSION

1. Physicochemical evaluation

The cinnamon-based roll-on formulation exhibited excellent physicochemical properties. The appearance was clear and uniform, with no visible phase separation or particulate matter. The color was consistent, showing a light yellowish brown shade, characteristic of cinnamon oil. The roll-on had a pleasant, sweet, and spicy fragrance, indicating the stability and presence of volatile components like cinnamaldehyde. The density was found to be within the acceptable range of 0.9 ensuring good consistency and ease of application. The volatile oil content remained stable, and no signs of rancidity or odor changes were observed during preliminary stability testing. Overall, the cinnamon-based roll-on passed all physicochemical evaluations, indicating it is stable.

Table no. 5: Physicochemical evaluation

Fig no.1 : Cinnamon powder and Roll-on

2. Stability Test

Table no.6: Stability testing

The cinnamon roll-on formulation exhibited good stability across various temperatures. At 4°C, the product remained physically stable with no phase separation. At 25°C, it maintained its appearance, fragrance, and therapeutic efficacy throughout the study period. Even under accelerated conditions (40°C), only minimal changes were observed, with no significant loss of volatile oils or product integrity is essential to establish shelf life, optimize formulation stability, and determine appropriate storage recommendations.

Fig no 2 :Under Refrigerator condition

3. Clarity Test

The clarity test was performed to assess the physical uniformity and visual appearance of the cinnamon-based roll-on formulation. The formulation was observed against a black and white background under adequate lighting. It appeared completely clear and transparent, with no visible particulate matter, phase separation, or turbidity. The absence of suspended particles and any signs of crystallization indicated that all ingredients were uniformly dissolved or dispersed within the formulation.

Table no. 7: Clarity test

Fig no. 3 : Clarity test

Clarity refers to the transparency or clearness of a formulation. It is an essential aesthetic and quality parameter, especially for semi-solid or liquid topical products. A clear formulation is often perceived as more appealing and indicates proper solubilization of ingredients.

4. Irritation Test

Table no.8 : Irritability test

Fig no. 4 : Patch irritabilty test

Irritability testing is performed to ensure that the formulation does not cause skin irritation or adverse reactions upon application. This is critical for topical products used on sensitive skin areas, such as during menstruation. The irritation test was conducted to evaluate the skin compatibility of the cinnamon-based roll-on. A small amount of the formulation was applied to the forearm of healthy volunteers and observed over a period of 24 to 48 hours. Throughout the observation period, no signs of redness, itching, swelling, burning sensation, or any other adverse skin reactions were noted. The formulation was well-tolerated, and the volunteers reported a soothing and mild warming effect, which is characteristic of cinnamon oil. Based on these observations, it was concluded that the cinnamon-based roll-on is non-irritant.

Method

Patch Test on Human Volunteers (Ethically approved):

A small amount of formulation is applied to the inner forearm or behind the ear.

The site is covered with a patch for 24 hours.

Redness , Itching and Irritation not occurred.

5. Spredabilty Test

Table no. 9 : Spredabilty test

Fig no.5:  Spredabilty test

Spreadability directly affects patient compliance and the therapeutic effectiveness of the formulation, as better spreadability ensures uniform application and efficient absorption.The slip and drag method was used. The spreadability of the cinnamon-based roll-on was evaluated to ensure ease of application on the skin. A small quantity of the formulation was placed between two glass slides, and a standardized weight was applied for a fixed time. The area covered by the roll-on formulation was measured. The results showed that the roll-on spread smoothly and evenly without requiring excessive pressure. The formulation exhibited excellent spreadability, forming a uniform thin layer, which ensures effective coverage over the affected area. These results indicate that the cinnamon-based roll-on provides easy application and good skin adherence.

6. Microbial Test

Table no. 10 : Microbial growth

Fig no.6 : Microbial test                                        Fig no.7 : Laminar Air Flow