When it comes to choosing between glass and plastic packaging for pharmaceutical products, most people will assume that glass is the best choice because of all of the negativity surrounding plastic and the impact it has on the environment. However, it is also worth considering the fact that while both materials can be recycled, there are greater limitations when it comes to recycling glass because it can only be turned into more glass. The truth is that it all comes down to application. There are some products whereby glass will be more suitable and there are others that are better being distributed in plastic packaging. With that being said, in this blog post, we are going to take a look at the suitability of glass and plastic bottles.
Glass bottles vs plastic
Glass and plastic are both well established primary packaging materials for the pharmaceutical sector. However, it is important to note that they both have their drawbacks. When choosing packaging, you need to make sure that your selection does not have a detrimental impact on the product. You also need to make sure that the product does not alter the properties of the packaging and impact its protective function.
Thankfully, a lot of medicines can be packaged in both plastic and glass. How well plastic or glass tolerates an active ingredient depends on its composition. There needs to be a careful examination of the drugs at an early stage. This should be carried out when clinical testing for the primary packaging starts. The pharmacist needs to make sure that all potential interactions between the packaging and the contents are recorded and risk assessed.
Depending on the application’s field, the pharmaceutical business may opt to use glass that is type I, type II, or type III. This will be based on the hydrolytic resistance that is needed. After all, it is not just a case of deciding between plastic and glass, you then need to decide what type of plastic or what type of glass is going to be best suited to the application. For example, you may find that amber glass is used to make a lot of cough syrup bottles, but then tubular glass is used for sterile ready to fill vials.
Now, let’s take a look at both materials in further detail and what they may be suitable for…
Currently, plastics constitute around 20% of the weight of all pharmaceutical packaging. There are many different types of uses for classic packaging. This includes:
- Cartridges, nebulisers, and vials
- Sachets, blister packs, and strip packs
- Flexible tubes
- Pre-fillable syringes
- Squeezable bottles for nasal sprays, eye drops, and eardrops
- Bags for parenteral solutions
- Plastic packaging systems for aqueous solutions
- Sterile plastic packaging systems for blood components and human blood
- Rigid bottles that serve as packaging systems for solid dosage forms, for example, capsules and tablets
As mentioned earlier, the use of pharmaceutical glass bottles is split into type I, type II, and type III glass. Glass type I can be used to package strong alkalis and acids. It is suitable for packaging material for most parenteral and non-parenteral preparations. Type II containers are suitable for most neutral and acidic aqueous preparations, whether parenteral or non-parenteral. Type III is used in non-parenteral preparations. It is only used for parenteral products where suitable stability test data indicates it is satisfactory.