Create an ER Diagram from the following structured description. Include entities, weak entities, relationships, min/max i.e. (1,N) ETC either with Visio, Paint or drawing with pen and paper. The following is the unstructured description in addition to the perceived entities and relationships below.

We want to create a database for a prescription system that doctors will use to prescribe medicine to their patients. During a patient visit, a doctor may write one or more prescriptions for medicine for the patient. The prescription will be filled by a pharmacy. Medicines may have side effects. The prescription for a specific medicine will include the number of pills, an amount to take and how often to take it. It will also include any other special instructions, such as whether or not to take the medicine with food. The prescription also includes an expiration date and prescription number. The prescription number uniquely identifies a prescription for a specific patient (i.e., the prescription number itself is not unique, it is only unique for a particular patient)