It is interesting to note that the aging dog (like his master) is also prone to prostatic enlargement, but (unlike his master) does not often develop retention of urine. However, due to the bulging upwards of the enlarged prostate the dog’s rectum is compressed. This engenders a feeling of continuous fullness in the rectum and induces straining. The prostates of eunuchs are small and underdeveloped, and enlargement of the prostate is unknown. Benign prostatic hyperplasia (BPH) is one of the most common diseases to affect men beyond the middle age. The prevalence goes up with age, and thus the total number of patients is increasing as a result of aging population. A majority of these people suffer gradual progression of symptoms and the concomitant discomfort, and require either medical or surgical treatment. The growth and development of the prostate is under the influence of male hormone “testosterone”. Rather surprisingly, there is no close correlation between the size of the prostate and the extent of outflow obstruction. However, the larger the prostate, the greater is the risk of BPH complications such as acute urinary retention and the need for surgery. BPH is usually a slowly progressive condition. An average increase in the prostate is 1-2 cm per year. BPH is the most common condition affecting the prostate accounting for over 80 per cent of prostate disease. The defined risk factor for BPH is age. Clinical BPH seems to run in families. In the early stages of the disease, the patient complains of hesitancy, a reduced stream and incomplete bladder emptying and then frequency, urgency and nocturia. Later on, prolonged micturition, acute urinary retention, urge incontinence, etc, can have a negative effect on the quality of life and may be associated with sexual dysfunction like erectile dysfunction and disorders of ejaculation. The treatment of BPH can be with the help of drugs or by going in for surgery. Some of the drugs used are Finasteride, Duatasteride, Terazosin, Alfuzosin and Tamsulosin. Adverse side- effects of these drugs can be erectile dysfunction, decreased libido, reduced ejaculation, drowsiness, headache, dizziness, postural hypotention, etc.