A sweat collection device includes an elongate concave sweat-collecting surface at a face thereof for placement over an iontophoresis-stimulated area of a patients skin to collect sweat and pass it through an axial bore in the concavity. A length of flexible tubing is secured to the axial bore for receiving and storing the collected sweat. A chamber may be provided for holding the tubing in flat coiled condition. Collected sweat builds up within the tubing from the axial bore. The device can include markings to indicate when a minimum amount of sweat has been collected in the tubing and can indicated a range for collected sweat that takes into account variations in the tubing. An open end of the tubing can be flared for easy insertion of a blunt needle to extract sweat or a guide passage can guide insertion of the needle into the open end of the tubing.