CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority under 35 U.S.C. § 119 from Italian Patent Application No. 102019000001703, filed on Feb. 6, 2019, in the Italian Patent and Trademark Office (“IPTO”), the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

This invention relates to a safety pen needle mainly usable to inject medication with an injection pen to be used, for example, by diabetic patients to make regular insulin injections.

STATE OF THE ART

In the state of the art, the use of a pen needle mounted on a vial containing a liquid to be injected is known. The injection is made with an injection pen which is coupled to the medication vial to exert on the liquid the necessary pressure in order to subcutaneously inoculate the liquid. The creation of an injection kit is also known. Said kit comprises a pen needle and a vial containing a medication to be injected.

The pen needle comprises a main body, a cannula and a shield. The main body extends in a longitudinal direction between a bottom and an opposite top and comprises a cavity which extends from the bottom to an opening placed at the top.

The cannula is placed inside the cavity and extends between a lower end, fixed to the bottom of the main body, and an opposite top end, projecting out of the cavity through the opening. The shield is configured to be reversibly coupled to the main body and to fully cover the top end of the cannula.

When in use, namely in case of injection, the vial is adapted to the bottom of the container to thereby allow the cannula to withdraw the liquid to be injected. An injection pen is coupled to the free end of the vial to compress the fluid contained inside the vial allowing the fluid to come out through the pen needle cannula. Once the shield has been removed from the main body of the pen needle, it is possible to proceed with the injection.

Problem of the Prior Art

After using a known pen needle, it is necessary to manually reposition the shield on the main body in order to protect the top end of the cannula. In addition, both before and after use, the pen needle is in the same configuration, namely with the shield covering the top end of the cannula. In detail, before use, the top end of the cannula is accessible by removing the shield from the main body. After use, there is a high risk of infection related to accidental punctures that could take place, for example right before disposal. In addition, once the shield has been removed, it is not possible to distinguish between an unused pen needle and one that has been already used so there is a risk of reusing the same pen needle more than once. Reusing the same pen needle involves the use of a cannula that is not sterile. This causes an increased risk of infection following an injection made with a contaminated cannula.

SUMMARY OF THE INVENTION

In this context, the technical task which forms the basis of this invention is to provide a safety pen needle which overcomes the drawbacks of the known art mentioned above.

In particular, the purpose of this invention is to provide a safety pen needle which prevents accidental punctures after the use of the pen needle.

In addition, the purpose of this invention is to provide a safety pen needle that allows to irreversibly cover the cannula of the pen needle after its use.

The purpose of this invention is also to provide a safety pen needle which allows to distinguish between an unused pen needle and one that has been already used.

Advantages of the Invention

Thanks to an embodiment of this invention, it is possible to irreversibly cover the cannula after using the pen needle, removing the risk of accidental punctures and preventing the reuse of the device. This prevents the risk of accidental punctures or contamination caused using the cannula of the non-sterile pen needle

Thanks to an additional embodiment of this invention, it's possible to distinguish between the configuration of the pen needle adopted before use from the configuration it adopts after the activation of the safety mechanism, in order to make the activation caused by the snap of the mechanism evident and to prevent further use.

