Medicated & Functional Chewing Gum

Medical professionals introduce medications and vaccines into the body via various sites, including directly into the veins or muscles. However, the mouth has come to the front as an area capable of providing an effective way to introduce various drugs into the human body.

Most of the attention has focused on direct ingestion into the gut via the mouth. Therefore, absorption into the bloodstream occurs across the gut lining. However, mucosal tissues line the mouth’s buccal cavity and sublingual areas, lending themselves well to absorbing medicines and vaccines and bypassing the first-pass metabolism. Read more about first-pass elimination.

In the Journal of Controlled Release, Kraan et al. discuss the various vaccines and drugs that the body can effectively absorb via the buccal and sublingual linings. Additionally, the paper expounds on the different dosage forms used to take advantage of these linings.

In this piece, we’re more interested in the controlled dosage forms. The review mentioned above focuses on orally disintegrating preparations and extended-release films and tablets.

Let’s take a closer look at how chewing gum can be an effective medicine delivery strategy.

What exactly is medicated chewing gum?

According to a review published in the Journal of Research in Medical Sciences, several studies have shown that chewing gum has been used as a drug delivery system from as far back as the mid-1920s. The advent of technology has seen this use become more standardized, streamlining its use as an extended-release dosage form.

As the decades have rolled by, the medicated chewing gum contents have morphed from rudimentary resins to sophisticated delivery systems.

When you break it down, all chewing gum comprises two parts; the water-insoluble gum base and the water-soluble bulk portion.

Let’s take a look at what each of them contains.

A. Water-Insoluble Gum Base

As the name suggests, the base is what holds everything together. It contains a host of other insoluble ingredients that enable the gum to maintain its structural integrity during chewing.

Here are the different ingredients in this gum portion.

• Elastomers: This gives the gum its characteristic elastic nature when a person starts chewing. For a long time, chicle extract from sapodilla trees was - and still is - used as a natural elastomer. 

However, with the advent of chemical engineering technology and a need to cut costs, synthetic elastomers have come to the fore.

• Plasticizers: These make the gum uniform and soft, enhancing the chewing experience for the patient. 

When added to the mixture, the plasticizers prevent the elastomer from cracking up. After all, they become brittle if they’re alone.

And just like elastomers, plasticizers can be natural or synthetic.

• Fillers: Fillers function as texturizers, adding texture. Additionally, they improve the gum’s chewability.

In medicated chewing gum, fillers increase the bulk if it’s a low dose medication.

B. Water-Soluble Portion

This part of the chewing gum contains active ingredients. Furthermore, the water-soluble part houses the contents that bring out a particular chewing gum’s nuanced taste profile.

Here’s what makes up this portion:

• Emulsifiers: These soften the gum, making it feel more stretchy when chewing. This is mainly through their ability to bind both portions together.

Since one part is hydrophobic and the other hydrophilic, it would be challenging to bind them in a uniform mixture. Emulsifiers achieve this uniformity.

• Sweeteners: To make medicated chewing gum an attractive proposition to patients, it needs to be palatable. Manufacturers add sweeteners to improve the gum’s taste.

Some sweeteners also double as binding agents and softeners. This is particularly true for aqueous sweeteners like sorbitol and corn syrup.

Furthermore, other sweeteners take on the role of bulking agents. Such sweeteners include sugars and sugarless components.

Bulking agents are used to beef up low-calorie gum.

• Flavoring agents: Most drugs have a disagreeable taste. To make them more pleasant to the tongue, flavoring agents are added.

Most flavors are based on familiar distinctive tastes. Therefore, medical chewing gum can taste like citrus fruits, peppermint or spearmint.

• Active ingredient: This is the drug of choice. Sometimes it is integrated into the gum’s core. Alternatively, it can be instituted into the coating.

Speaking of active components, medicated chewing gum has been used to deliver drugs to treat several conditions.

How is medicated chewing gum being used currently?

Medical professionals utilize the mouth cavity and area beneath the tongue for vaccine delivery. According to the earlier mentioned research review by Kraan, these areas are particularly ideal for introducing live attenuated and inactive vaccines and adjutants.

However, all these buccal and sublingual vaccinations are in the form of sprays and controlled release formulations like orally-disintegrating preparations and extended-release tablets.

Medicated chewing gum can also be an ideal controlled release formulation.

Currently, it’s applied for therapeutic uses. Below, we look at some of these uses alongside the active ingredients/drugs.

• Helping smokers quit their tobacco addiction (nicotine)
• Relieve pain (aspirin, silver acetate)
• Relive Allergies (Cetirizine)
• Reduce nausea and treat motion sickness (ginger, Bismuth subsalicylate, Dimenhydrinate )
• Treat oral fungal infections (miconazole)
• Improve alertness (caffeine, Ginkgo Biloba, Eleutherococcus senticosus )
• Improve oral and dental health (xylitol, chlorhexidine, Hydroxyapatite)
• Combat sepsis and inflammation (aloe vera)

Advantages of using chewing gum to deliver medication

Because of its effectiveness in dealing with the above conditions, medicated chewing gum is an ideal vessel for releasing drugs and other active ingredients into the mouth.

It poses several advantages over other forms of oral medication.

These include:

• Children are usually skeptical about tablets and pills. Chewing gum appeals to them more; they might not realize they’re taking medicine.
• No need for drinking water to swallow, making it convenient.
• Eliminates stomach upsets that occur when orally-administered drugs reach the stomach
• Chewing gum can deliver drugs for both local oral issues and systemic conditions.
• It’s ideal for patients who find it challenging to swallow.
• Ideal for fast-acting drugs because of quick absorption from the mouth’s lining
• Pain-killers like aspirin can cause peptic ulcers when swallowed. Extended release through chewing gum avoids this.
• Reduced side effects
• While most drug preparations need precise environmental conditions to remain viable, chewing gum is stable when exposed to light, moisture and temperature.
• The patient can stop dosing at any time by spitting out the gum.

Despite these benefits, chewing gum can also have some disadvantages. For example, sweeteners like sorbitol can cause flatulence and diarrhea. Additionally, one can experience facial pain from chewing for long.

This long chewing period also affects the drug amount absorbed. After all, the patient might want to eat or drink and speak.

What factors affect medicated chewing gum effectiveness as a drug delivery alternative?

Based on the benefits mentioned above, medicated chewing gum is a viable drug delivery medium. But like any other type of drug administration, there are factors that determine its effectiveness.

Here are the factors determining the effective release of the active drug ingredient from the chewing gum into the mouth.

Chewing time

With controlled-release formulations, you need a longer exposure time to ensure that the body has absorbed a sufficient drug amount. When it comes to medicated gum, the patient needs to chew for an average of a half-hour.

However, some patients might find this too long to chew a piece of gum.

Therefore, manufactures would need to have different kinds of gum with different chewing profiles depending on the drug type in question.

Drug/Active ingredient physicochemistry

Various drugs and active ingredients have different physicochemical properties. In this instance, we’re interested in their interactions with water and lipids.

Some active components in chewing gum are highly soluble in water, whereas others are insoluble in water but soluble in lipids.

Water-soluble ingredients are released quickly into saliva and absorbed into the body. On the other hand, lipid-soluble active components first dissolve into the gum base before slowly releasing into the mouth.

Gum formulation

As we’ve noted above, the drug’s physicochemical properties affect its release and dissemination into saliva.

Manufacturers can also take this into account when formulating medicated chewing gum. To make extended-release gum, they can alter the formulation by integrating more lipids into the gum base.

Alternatively, by reducing the lipid content, they can make a quick-release medicated chewing gum.

The patient’s chewing form and habits

Everyone chews differently; the frequency, speed and intensity vary. Some people chew harder but slower, whereas others chew faster and lighter. All these factors affect the drug’s release.

For instance, a review on medicated chewing gum by Chaudhari and Shahiwala states that a frequency of one chew per second releases more nicotine than 1 chew per 8 seconds.

Where to from here?

Medicated chewing gum has shown legitimate benefits as a drug delivery system. It has grown from treating oral ailments to controlling systemic conditions.

As technology progresses, it’ll be possible to treat various other systemic physical and psychological conditions. Furthermore, it might become possible to deliver several active ingredients in one chewing gum pellet.

If you are interested in manufacturing functional gum:

?Jake Ribbe

Direct: 619-732-0806

[email protected]

References:

https://www.sciencedirect.com/science/article/pii/S0168365914003861?via%3Dihub

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4468459/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3970722/

https://www.researchgate.net/publication/44685425_Medicated_chewing_gum_-_a_potential_drug_delivery_system