I had botox for leaking parotid gland after facelift, and there's no improvement. Has it drained out?

Botox can be used to decrease salivary production after a parotid gland injury so that the capsule can heal, sealing the leak. 
To ensure you are receiving the highest level of care, seek out a modernly trained, new-school dermatologic surgeon, oculoplastic surgeon, facial plastic surgeon or plastic surgeon who is board certified and fellowship trained in one of these “core four” cosmetic specialties. Membership in organizations like the American Academy of Facial Plastic and Reconstructive Surgery help to identify a highly trained surgeon.
Cameron Chesnut
#realself100 Physician

Botox is used in treatment of Frey syndrome after parotidectomy. salivary leak after facelift may be due to duct injury and would not respond to Botox. 

Botox can be injected into the parotid to limit salivary production. Anticholinergics can also be used. Best of luck.