How it works: Insulin lowers blood sugar by moving sugar from the blood into the cells of your body. Once inside the cells, sugar provides energy. If you take insulin, you'll need to eat on time and match your insulin injections to your meals. Your insulin should peak at the same time blood sugar levels from meals are also peaking.
Work with your health care team to establish a meal plan and to work out how to take your insulin in relation to your meals. It's important to plan for those 'what if' situations that come up and to know what to do. A few basic tips include:

• Remember, you need some insulin in your body all of the time.
• You need some insulin before you eat a meal. Match the dose to the estimated amount of carbohydrates in the meal. Your diabetes educator can show you how.
• You may need additional insulin to lower your blood sugar if it is high sometimes.
• By testing your blood sugar at least four times a day, you'll have the knowledge you need to moderate your insulin, activity and eating so that your blood sugar is under good control.

A rough guideline to remember is that one unit of insulin lowers blood sugar by 50 mg/dL and covers about 10 to 15 grams of carbohydrate. Most people with diabetes need at least two insulin shots a day for good blood sugar control. Some people take three or four shots a day to have a more flexible plan.

You should take insulin 30 minutes before a meal if you take regular insulin alone or with a longer-acting insulin. If you take lispro (Humalog), or insulin aspart (Novolog), two insulins that works really fast, you should take your shot just before you eat.

Very Fast acting - The fastest acting insulins are called lispro (Humalog)and insulin aspart (Novolog). They should be injected under the skin within 15 minutes before you eat. You have to remember to eat within 15 minutes after you take a shot. These insulins start working in five to 15 minutes and lower your blood sugar most in 45 to 90 minutes. It finishes working in three to four hours. With regular insulin you have to wait 30 to 45 minutes before eating. Many people like using lispro because it's easier to coordinate eating with this type of insulin.

Fast acting - The fast acting insulin is called regular insulin. It lowers blood sugar most in 2 to 5 hours and finishes its work in 5 to 8 hours.

Intermediate acting - NPH (N) or Lente (L) insulin starts working in one to three hours, lowers your blood sugar most in six to 12 hours and finishes working in 20 to 24 hours.Long Acting – Lantus is a new true once a day background insulin from Aventis Pharmaceuticals. It represents a remarkable breakthrough in that it is the first insulin to offer truly flat insulin levels through the entire day for most users. Considered an alternative to an insulin pump, it is the first long-term insulin that has a predictable and consistent insulin activity. Aventis recommends taking Lantus at bedtime, although recent research has shown that it's activity is slightly improved when taken in the A.M. Lantus' actual duration of action is 18 to 26 hours. Although the timing varies from individual to individual, it appears to be consistent in the same individual. It's job is usually less than dramatic, not responding to the turmoil, crises and carbohydrates of life like Regular (fast acting) or Humalog (very fast acting). It's usually the last thing you adjust to solve a problem. But there are times when adjusting the long-acting or basal insulin has to be considered.

Insulin Mixtures - There may be advantages of using insulin mixtures and these should be discussed with your doctor.

People don't respond to individual types of insulin the same way. So, working with your doctor, you have to find the right insulin or combination that works for you. Your insulin choice should dovetail with your eating and exercise patterns, so it's important for you to plan your insulin intake with your doctor or diabetes educator.

Most people who use insulin inject it with a needle and syringe, but there are several other devices that are available. These include:

• Insulin pens - These are handy if you want the convenience of carrying insulin with you in a discreet way. An insulin pen looks like a cartridge pen. Some pens use replaceable cartridges of insulin and other models are disposable. The tip of the pen has a fine, short needle. Users turn a dial to select the desired dose of insulin and press a plunger on the end to deliver the insulin.
• Insulin jet injectors - These send a fine spray of insulin through the skin by a high-pressure air mechanism instead of needles. These are great for people who fear needles, but they're expensive and you have to boil and sterilize the units frequently.
• External insulin pumps - These connect to narrow, flexible plastic tubing that ends with a needle inserted just under the skin near the abdomen. The insulin pump is about the size of a deck of cards, weighs about 3 ounces, and can be worn on a belt or in a pocket. Users set the pump to give a steady trickle or 'basal' amount of insulin continuously throughout the day. Most pumps have the option for setting several rates. Pumps release bolus doses of insulin (this means several doses at a time) at meals and at times when blood sugar is too high based on the user's programming. If you use an insulin pump, it's really important to monitor your blood sugar frequently so you can determine the right dose and also to be sure that the insulin is being delivered. These pumps can be expensive to buy and maintain.