Ampules vs. Vials: Best Practices in Handling and Usage

Ampules are small cylindrical glass or plastic containers that store and preserve pharmaceutical drugs, chemicals, and other medical-related solid and liquid substances. Vials are like ampules, except they are larger, reusable containers. Since you must crack open ampules to access their contents, they are unusable afterward.

Medical and nursing students will gain much experience working with ampules and vials because they are commonly used to store medication. Below are the top six best practices in handling and using ampules and vials.

1) Ampules are Better for Single-Dose Storage

Ampules are temporary containers meant for storing a single dose of medication. Each ampule container has a bottom vessel for storing the medicine, a sealed neck area above it, and an extended, narrow top portion.

When preparing an ampule, heat is applied to the neck area to seal it between the top and bottom portions of the container. To open the container, apply pressure to the top portion to crack it open at the neck. Then, you can access its contents through the newly opened neck area.

The bottom vessel of the ampule has enough storage space to hold one dose of a medication. Once used, throw away the ampule because the top has snapped off and cannot be put back on again. There is no way to screw it back on like you can with a vial container. 

2) Sterilize the Vials

Vials are multi-dose medical containers. You can fill them up with medication, screw on the cap, and then store them safely. When ready to use a vial, apply pressure to the cap as you twist it simultaneously. The cap should come off if you do it correctly. Then, you can access the contents inside the vial.

Vials are reusable, so you do not have to throw away a vial after using its medicinal contents. However, you must clean and sterilize the vial before adding new medicine to the container. Otherwise, you could contaminate the vial with other medicine unrelated to the new medicine you add next time. Unintentionally combining medicine is never suitable for the patient who consumes it.

There are a few ways to sterilize vials. The most popular way is to put the used vials in a hot air oven or autoclave and set it to a temperature of 320°F. Leave the vials in there for about 2 to 3 hours. Most doctors and scientists believe heat is the most effective sterilization method for glass vials.

On the other hand, excessive heat could melt the plastic and ruin the vials if you need to sterilize plastic vials. You are better off using a chemical-based sterilizer like hydrogen peroxide, isopropyl alcohol, or bleach to sterilize the vials. If you still want a heat-based method, put the plastic vials into boiling water for 5 to 10 minutes. Afterward, use soap and water to wash the vials and rinse away the soap suds.

3) Ampules are Better for Preventing Contamination

Ampules do better at preventing contamination because the neck is moulded shut with a heat application. No one will be opening and closing ampule caps repeatedly, as you see with the screwable caps of vial containers. Ampules are sealed airtight for as long as the neck remains uncracked. That means there is no risk of any contamination whatsoever.

For this reason, ampules are better for storing more sensitive medicines and chemicals with unstable compounds. Their robust sealant protection helps ensure that no oxygen or contaminants will mix with the unstable compounds and cause an adverse reaction. Just try to access the contents within a reasonable time because ampules are not meant for long-term storage.

4) Vials are Better for Storing Stable Chemical Compounds

Stable compounds do not react when exposed to oxygen or most contaminants. That is why vials are better for storing medicines and chemicals with stable compounds since opening and closing the cap will not cause an adverse reaction. Some examples of stable compounds include silver nitrate, carbon monoxide, copper oxide, zinc sulphate, sodium chloride, and water.

Theoretically, you could store stable compounds inside ampules, but you won’t have as much storage space as you would with vials. So, you might as well use vials to hold multiple doses of medicine and other critical substances with stable compounds.

5) Use Syringes for Exact Measurements to Fill the Containers

Syringes are the most common medical instrument used to obtain exact measurements of liquid substances to add to ampules and vials. The ampules begin with open necks for inserting liquid medicines or other substances into them. After inserting the liquid, the existing air is extracted from the ampules, and the neck is sealed with a heat application. As for the vials, you can unscrew the cap and inject the liquid substances into them as needed. There is no threat from air exposure here.

6) How to Snap the Neck of an Ampule Properly

Be careful when snapping the neck of an ampule because improperly opening it could cause its liquid contents to splash out. Don’t leave it open for too long because the exposure to oxygen could cause an adverse reaction and ruin the contents inside.

The best way to open an ampule is to gently rub a nail file around the neck to give it a light scratch. Then, gently wipe the ampule with a fresh alcohol swab until the exterior is clean. Next, ensure all the liquid contents sit at the bottom of the ampule. No liquid should be in the top portion. If there is, flick the top portion with your finger a few times to knock the liquid droplets down into the bottom portion.

Grab a gauze pad and use it to grip the top portion of the ampule. The gauze should wrap around the entire top half as you grip it with your fingers tightly. Use your other hand to grip the bottom half of the ampule firmly. Use your fingers to pull and bend the top portion toward your direction until it snaps off. Be prepared for the possibility of broken glass pieces flying out.

Conclusion

Keep your ampules and vials stored in a dry, well-ventilated location at room temperature. Remember to label your ampules and vials with the proper details regarding their contents. That way, you can prevent the risk of someone using the contents without knowing what it is.