Abstract: Lactation of pseudopregnancy is a common condition presented for treatment, especially in dogs displaying behaviour that their owners find annoying. Prolactin antagonists are often effective and signs are eliminated within 10 days after the start of treatment. However, drug interactions, mechanical or sensory stimulation of milk secretion, endocrine disorders (hyperoestrogenism, hypothyroidism, etc..) or ovariectomy performed during the luteal phase, all of which promote milk secretion, can be refractory to treatment.