Both adrenaline injector brands have windows on the devices to check to see what the medication inside the device looks like.
It is better that you check the colour of the fluid when it is not an emergency, for example check the fluid when you check the device expiry. A&AA recommend you routinely check your device to make sure it is still okay and has not expired.
It is better to know that the device you are carrying is in good condition than find something is not right when you need to use it for anaphylaxis.
Discoloured or expired adrenaline injectors don’t work as well and should not be relied on to treat anaphylaxis BUT if a discoloured or expired adrenaline injector is the only one available it is better to use this rather than no adrenaline injector.