An automatic injection device with flow regulation. The automatic injection device has an insertion needle configured to be inserted into a patient and a drug container which contains a pharmaceutical product and includes a plunger. The automatic injection device also has a fluid path which fluidly connects the drug container to the patient via an insertion device, a potential energy source, and a regulator configured to restrict release of potential energy and restrict linear movement of the plunger and pharmaceutical product into the fluid path at a proscribed pace. The regulator includes a clock escapement mechanism. The potential energy source may be a spring that surrounds the drug container and may be magnetically coupled to the plunger. The clock escapement mechanism is configured to control the spring at a regulated rate over a time interval using a gearbox and rotational- to-linear translator comprising a rack and pinion.