To preserve means to slow down the process of deterioration. Prevalent in the food and beverage industry; cosmetics and pharmaceuticals industry, preservatives are added to help keep the products sterile and stable for longer periods of time. They work by inhibiting the growth of bacteria and by preventing product decomposition, both of which are processes that would lead to alterations that would have a negative impact on the quality of the product.
The Role of Preservatives in Pharmaceutical Products
Traditionally speaking, preservatives used in pharmaceutical products are added to those that have higher water content and serve two purposes, firstly to keep the product sterile and secondly, to prevent the degradation of the product over time.
Keeping the pharmaceutical product sterile requires that the chemical substance added to it be able to keep it free from microorganisms such as bacteria and fungi, which can cause disease and infection.
On the other hand, degradation of pharmaceutical products happens when the product comes in contact with oxygen. As this happens the product goes through the process of oxidation, which alters its stability and ultimately its healing function.
The use of preservatives has until recently been a necessary must for the pharmaceutical industry to produce sterile and stable products. However, preservatives are associated with unwanted side-effects.
What are the Harmful Effects of Preservatives?
Unfortunately, while preservatives are effective at keeping pharmaceutical products sterile and stable, they’ve become counterproductive to the ailments they are trying to heal. The two most common uses of preservatives in medicines are in ophthalmic eye drops and nasal sprays.
Ophthalmic eye drops used to treat dry eyes, glaucoma and eye allergies contain preservatives specifically designed to keep the medication sterile during use for the entire life cycle of the bottle. Unfortunately, the preservatives are very effective against bacterial growth but are not specifically designed to be friendly to the eye.
Preservatives within eye drops are known to
– Damage the tear film
– Cause eye allergies
– Inhibit healing of damaged eye cells such as the corneal epithelium
– Be incompatible with contact lenses
Long-term use will lead to poor production of the tear film, which will result in dry eyes syndrome. It can also roughen the cornea, which can then lead to foreign body sensation and deteriorating vision.
The use of preservatives in nasal sprays remains controversial, with medical studies documenting their harmful effects. Preservatives in nasal sprays commonly tend to cause nasal allergies. Medical studies show that preservatives found in nasal sprays may impair one of the most important local defence mechanisms of the respiratory tract, mucociliary clearance. In simple terms, our respiratory tract is covered by small projecting “hairs” called cilia. These cilia create motions which drain mucus from the nasal passage to the throat from where it is swallowed and digested by stomach juices. Preservatives used in nasal sprays have been found to be toxic to these cilia thus inhibiting them from creating the motions that drain the mucus out of our nasal passages.
Do Preservative Free Eye-Drops and Nasal Sprays Exist?
In short, yes. Today, pharmaceutical companies developed eye drop and nasal spray delivery systems specifically designed to block microbial contamination without the use of preservatives. How?
By mechanically preventing atmospheric air from entering the bottle and contaminating the medication stored within it, even for long-term use.
These innovative patented delivery systems now allow the production of sterile and stable medicinal products without the use of preservatives and their unwanted effects.