Panara does not act as a middleman when it comes to sending SMS messages. The program simply facilitates the sending of SMS messages from accounts that users independently set up with an SMS Gateway company. We support 2 such gateways in the program (Kapow and Clickatell.)
So the cost of an SMS recall or appointment reminder is the cost the gateway charges for a text message with nothing added.
Yesterday I received an email from Clickatell advising of new pricing for messages sent to irish mobiles
Below I have reproduced the same information taken from their website

At 2.08 cent per message (about 2.5 after VAT) I think this must be the cheapest available.
As of the update (2.2.6) released today you can now swipe the information on the back of Medical cards directly into a patient’s record in Panara.