Let's take a minute to talk about your medication. This is Humulin 70/30 in a Kwikpen. Humulin 70/30 is a mixture of two different insulins. It lowers blood sugar in people with diabetes. It starts working in about 60 minutes, and the effects can last for several hours. You should use this medicine exactly as your doctor tells you to. Your doctor will teach you how to inject a dose. You should read the full 'Instructions for Use'. Before each dose, you should remember to do two things: - Read the label on the Kwikpen to make sure you are using the correct insulin. - And, you must gently roll and invert the Kwikpen to make the medicine cloudy. If you still have questions, your doctor or pharmacist can help. Most people tolerate this insulin well. Common side effects include weight gain and mild reactions at the injection site, like redness, swelling or itching. At first, some people may notice mild swelling of the hands or feet. Over time, this insulin can cause the skin to have lumps or scar tissue. You can reduce skin problems by rotating injection sites. As with any medicine, more serious side effects could occur. With Humulin 70/30, these include an allergic reaction and low blood sugar. You should read the patient information sheet to know which symptoms to watch for. Also, you should make a plan with your doctor to manage blood sugar levels when they are low or high. You should check with your doctor before you take other medicines, before you drink alcohol, and before you travel. Also, you should always call your doctor if you become sick or stressed, or if you have changes to your diet, weight or exercise level. For best results with Humulin 70/30, follow your doctor's orders for checking your blood sugar.