Other common side effects of Herceptin, occurring in less than 10 out of 100 patients, are: allergic reactions, abnormal blood counts (anaemia, low platelet count and low white blood count), constipation, heartburn (dyspepsia), infections, including bladder and skin infections, shingles, inflammation of the breast, inflammation of the pancreas or liver, kidney disorders, increased muscle tone / tension (hypertonia), tremor, numbness or tingling of the fingers and toes, nail disorders, hair loss, inability to sleep (insomnia), sleepiness (somnolence), nose bleeds, acne, itchiness, dry mouth