Shannon, the site removed your post at "Our eat ***** ***** seems..." Can you clarify which breed and age your dog is, please?
I believe he suffers from canine pedal furunculosis which aren't cysts but, instead, furuncles, a form of deep pyoderma.
1) The initiating cause of the furunculosis (e.g. food allergy, wet environment, dirt kennels, friction in short-coated breeds) should be identified and corrected.
2) If draining lesions are secondarily infected, appropriate antibiotics or antifungal medications should be administered for a minimum of 4-6 weeks. Cephalosporins such as cehalexin and fluoroquinolones such as enrofloxacin are usually good choices.
3 For solitary lesions, surgical excision or laser ablation may be curative.
4) Cleansing wipes (alcohol-free acne pads, baby wipes, chlorhexidine-containing pledgets, or other antimicrobial wipes) used every 12-72 hours work very well. For interdigital bullae, surgical removal of the ruptured hair follicle and 'ingrown" hair with a biopsy punch or laser speeds resolution. Fro developing bullae, topical dimethyl sulfoxide (DMSO) combined with enrofloxacin (to make a 10mg/ml solution) and steroid (dexamethasone or fluocinolone) should be applied every 12-72 hours until lesions resolve. To prevent recurrence, the feet should be wiped or scrubbed in the direction of hair growth to remove any "ingrown" hairs.
5) Alternatively, treatment with combination tetracycline and niacinamide may be effective in some dogs. A beneficial response should be seen within 6 weeks of treatment initiation. Administer 500mg of each drug (dogs>10kg) or 250mg of each drug (dogs<10kg) every 8 hours until lesions have resolved (~2-3 months). Then administer each drug every 12 hours for 4-6 weeks, subsequently attempting to decrease frequency to every 24 hours for maintenance. Anecdotal reports suggest that doxycycline 10mg/kg should be administered every 12 hours until response occurs, then tapered to the lowest effective dose. (doxycycline may be substituted for the tetracycline above but given twice instead of three times daily).
6) Anecdotal reports suggest that treatment with cyclosporin 5mg/kg administered every 24 hours may be effective in some dogs.
7) For severe, nonsurgical, or multiple lesions, treatment with glucocorticoids may be effective. Prednisone 2-4mg/kg should be administered every 24 hours. Significant improvement should be seen within 1-2 weeks. After lesions have resolved (~2-3 weeks) the steroid dose should be gradually tapered.
The prognosis is good to fair. Lifelong medical therapy may be needed to maintain remission, and interdigital fibrosis may be a permanent sequela in chronic cases. If his vet isn't familiar with this skin disorder, referral to a specialist veterinary dermatologist (please see here: www.acvd) should be considered. This can be a very difficult, time-consuming, and expensive disease to manage properly and a specialist can zero in on the best therapy without multiple trial and errors.
Please respond with further questions or concerns if you wish.