Hi, Regards !
Thanks for your query.
The diagnosis is certainly
Post Herpetic Neuralgia PHN as you have written.
Considering your age which is 78 years, the dose of
Lyrica 150 mg is high enough in the elderly.
The swelling indicates that the inflammation is still present and the internal healing is not yet complete.
The pain of PHN is more in the elderly people like you, takes far more time than the young adults would take for recovery, control of pain and other symptoms.
I would advise such a patient :
Neurologist's opinion and further management.
Discuss about the trial of other medicines like
Gabapentin / Amitryptiline - Tegritol or so, any role of other procedure that can reduce the pain.
Alternative therapy like Yoga, Acupressure or
Acupuncture can help a lot in reduction of the stress and
anxiety of the person who is suffering from this.
I hope this answer helps you to visit the Neurologist and get the proper investigations and and treatment.