A kit to be used for medical treatment is disclosed. The kit comprises aplurality of penneedles adapted for giving an injection to a patient, such as insulin, and acompartmentadapted to contain and provide said plurality of pen needles. Each pen needlecomprises acoloured mark for being distinguished from at least one other pen needle ofthe kit havinga different color mark, whereby in use, the patient selects the desired penneedle infunction of a colour of the coloured mark. A tattoo assembly is alsodisclosed. It can beused in conjunction with the coloured pen needles as it comprises a pluralityof guidingnon-permanent tattoos adapted to be affixed on a body injection site of thepatient andhave a colour and/or a shape to assist the patient in selecting a given bodyinjection site.Methods for treating diabetes are also disclosed.
