Hello, •     Brief Answer: Butalin can cause uncontrollable shaking of a part of the body.Detailed Answer: Butalin Syrup is a prescription medicine that is used to prevent & treat wheezing, narrowing of the airways, chest tightness, difficulty breathing, and coughing caused by lung diseases such as asthma, and long-term obstructive pulmonary disease. This medicine works by relaxing and opening the muscles of the airways. Butalin Syrup is also used to treat damaged and enlarged air sacs of the lungs and long-term inflammation of the bronchial tubes. •     Other side effects are: chest pain •     difficulty falling asleep or staying asleep •     dizziness •     dry mouth •     excessive tiredness •     fast or irregular heartbeat •     headache •     lack of energy •     low levels of potassium in the blood •     nausea •     nervousness •     seizures I suggest you see a doctor. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr Enton Dore, General & Family Physician