Don't use Elasticsearch or use it with caution if:

• You are looking for catering to transaction handling.
• You are planning to do a highly intensive computational job in the data store layer.
• You are looking to use this as a primary data store. If this is a requirement, when data is inserted, Elasticsearch has to re-index and this would take some time and wouldn't be available as and when the data was inserted and updated.
• You are looking for an ACID compliant data store.
• You are looking for a durable data store.