Hi and welcome,
As you have mentioned you have sore area on the side of the tongue , this indicates formation of ulceration . tongue ulcers may be caused by several reasons like stress related ulcers ,deficiency of vitamins, apthous ulcers , trauma from adjacent tooth bite or sharp cuspal areas of the teeth often lead to ulcers on the sides of the tongue .
As u said your dentist
has put you on acyclovir
shows the viral infection like herpetic ulcers.
I suggest you to start with multivitamin
supplement and vitamin C lozenges 2 times daily for 7 to 10 days.
you can apply oral antiseptic gel like mucopian or dentogel topicaaly over the ulcerated areas that will help in healing . Use mouth rinses
for rinsisng the mouth that provides soothing effect , removes the bad odour and prevents secondary infection.
i hope this helps you , get well soon .