Outpatients with short-term antibiotic treatment should start and finish the treatment according to medical advise that is, the intake pattern (named adherence) should be regular. The research question is: Can a smartphone-based program including intake reminder and two text messages improve adherence to a short-term antibiotic treatment in ambulatory setting?

Participants will be asked to record every antibiotic intake in an app on their smartphone over the prescribed therapy duration and to note their symptoms once daily. One group will obtain reminder + text messages, and the control group will have no reminder + no text messages.

This study is planned as a monocentric, cluster-randomized, double-blind, two-arm study in a primary care setting with outpatients newly prescribed co-amoxicillin for a short-term therapy. Participating community pharmacies will recruit patients entering with a prescription for co-amoxicillin and offer the service. Randomisation will take place on the pharmacy level via computer generated list of numbers (1: with intervention; 2: with no intervention). Pharmacists and participants will not know that the intervention is not the app itself, but rather the combination of a reminder and text messages (= double-blind). The intervention will consist of the use of a smartphone reminder (e.g. alarm clock or a reminder app; a list with suitable examples will be given and patients will choose one of them) and two personalized motivational and educational text messages that will be sent by the pharmacy during the treatment duration. The control group will have no reminder and no text messages. All participants will use a simplified version of the freely available medication management app TOM to record their medication intake (= adherence measurement method). Participants in both groups will obtain a consultation driven by their adherence report with the study team at the end of the treatment to discuss their individual adherence data, their symptom course and well-being. After that, patients will receive a link to an online survey where they will evaluate their satisfaction with the service and the smartphone application. Participating pharmacists will be interviewed by the study team regarding their experience and satisfaction after the end of the study.

Inclusion Criteria:

• is min. 18 years old;
• is newly prescribed a co-amoxicillin treatment of 3-14 days;
• has symptoms that correspond to bacterial infection;
• accepts to use of one of the medication adherence application with reminder function from the provided list;
• accepts to use of the electronic monitoring application TOM™ during the study period;
• is capable of using the TOM™ application;
• signs the informed consent form;
• understands and speaks (Swiss) German.

Exclusion Criteria:

• in the opinion of the pharmacists, unlikely to comply with the study schedule or are unsuitable for any other reason.
• does not manage medication himself/herself
• already using a medication intake reminder