Trish McEvoy Intense Gel Eye Liner

Q: Can this eyeliner be applied to the lower waterline and actually stay on?

Yes it is ideal for lower waterline and it will stay on

Q: How long can it be used?

Not sure what you mean by your question, but mine lasts months and months before I have to replace it. It comes with a sharpener that you use to expose the 'crayon' when it gets too flat to line your eye. I've been using it for years (aubergine color) and even though expensive, wouldn't consider using anything else; absolutely super product!

Q: How are you supposed to sharpen the gel? It seems to run out after 10 uses and theres no way to push up the gel past the plastic part

It comes with a black pencil sharpener in the box. Use the pencil sharpener to sharpen the gel. I almost missed mine in the bottom of the box. I hope you didn’t throw it away!