An Introduction to Insulin

An Introduction to Insulin: What is It and How Does it Work

Insulin is a hormone produced by the pancreas that plays a critical role in regulating the levels of glucose in the blood. Glucose is a source of energy for the cells in the body, and insulin helps ensure that the cells receive enough glucose to function properly. 

What is insulin? 

Insulin is a hormone produced by the pancreas, which is located in the abdomen behind the stomach. Insulin is produced by specialized cells in the pancreas called beta cells. Insulin plays a crucial role in regulating the metabolism of glucose (sugar) in the body. When we eat food, especially carbohydrates, our body breaks down these carbohydrates into glucose. The glucose is then absorbed into the bloodstream and travels to the body's cells, where it is used as a source of energy.

How does Insulin work? 

When you eat, your digestive system breaks down food into glucose and other nutrients, which enter your bloodstream. As glucose levels rise, the pancreas releases insulin, which signals the cells in your body to take up glucose from the blood. Insulin works by binding to receptors on the surface of cells and triggering a series of events that allow glucose to enter the cell.

Once inside the cell, glucose can be used for energy or stored as glycogen for later use. Insulin also stimulates the liver to store glucose as glycogen and reduces the liver's production of glucose. In this way, insulin helps regulate blood glucose levels and prevent them from becoming too high (hyperglycemia) or too low (hypoglycemia).

Insulin and Diabetes 

Insulin is a hormone produced by the pancreas that regulates the metabolism of glucose (sugar) in the body. Insulin plays a crucial role in maintaining normal blood sugar levels and allowing cells to use glucose for energy. Diabetes is a chronic condition that occurs when the body either does not produce enough insulin or cannot effectively use the insulin it produces. This leads to high levels of glucose in the bloodstream, which can cause a range of health problems.

Types of Diabetes

There are two main types of diabetes: type 1 and type 2.

Type 1 diabetes: This type of diabetes is an autoimmune condition in which the immune system attacks and destroys the insulin-producing cells in the pancreas. People with type 1 diabetes require lifelong insulin therapy to regulate their blood sugar levels.

Type 2 diabetes: This type of diabetes is characterized by insulin resistance, in which the body does not effectively use the insulin it produces. Over time, the pancreas may produce less insulin, leading to high blood sugar levels. Type 2 diabetes can be managed through lifestyle changes, such as diet and exercise, and medication, including insulin therapy.

Insulin is a key player in the management of diabetes. People with type 1 diabetes require insulin therapy to regulate their blood sugar levels. They may need multiple daily injections of insulin or an insulin pump, which delivers insulin continuously throughout the day. Insulin therapy aims to keep blood sugar levels within a target range to prevent short- and long-term complications.

For people with type 2 diabetes, lifestyle changes, such as diet and exercise, may be enough to manage their blood sugar levels. However, some people with type 2 diabetes may also require insulin therapy if their blood sugar levels are not well-controlled with lifestyle changes and oral medications.

Learn more about Diabetes: Diabetes

Synthetic Insulin

Synthetic insulin, also known as recombinant insulin, is made to treat people with diabetes mellitus who require insulin therapy. Synthetic insulin is made to mimic the function of natural insulin in the body and help regulate blood sugar levels.

Before the development of synthetic insulin, insulin was extracted from the pancreas of cows or pigs and then purified for use in humans. While this method was effective, it posed some risks, including the potential for allergic reactions and the risk of transmitting diseases from animals to humans. Synthetic insulin, on the other hand, is created in a laboratory using recombinant DNA technology, which allows for a more precise and controlled production process.

Insulin Types and Administration

There are several types of synthetic insulin, including rapid-acting, short-acting, intermediate-acting, and long-acting insulin. Each type has a different onset and duration of action, which allows for better management of blood sugar levels.

The types of insulin and their uses are as follows:

A.) Rapid-acting insulin: This type of insulin begins working within 15 minutes after injection and peaks in 1-2 hours. It typically lasts for 3-5 hours. Rapid-acting insulin is often used to control post-meal blood sugar spikes or to correct high blood sugar levels.

B.) Short-acting insulin: This type of insulin begins working within 30 minutes after injection and peaks in 2-3 hours. It typically lasts for 3-6 hours. Short-acting insulin is used to control blood sugar levels before meals.

C.) Intermediate-acting insulin: This type of insulin begins working 2-4 hours after injection and peaks in 4-12 hours. It typically lasts for 12-18 hours. Intermediate-acting insulin is often used to control blood sugar levels between meals or overnight.

D.) Long-acting insulin: This type of insulin begins working several hours after injection and lasts for up to 24 hours. Long-acting insulin is used to provide basal insulin coverage throughout the day and night.

E.) Ultra-long-acting insulin: This type of insulin begins working several hours after injection and lasts for up to 36 hours. Ultra-long-acting insulin is used to provide basal insulin coverage for people who need extended insulin coverage.

F.) Combination insulin: This type of insulin combines two different types of insulin (usually rapid-acting and long-acting insulin) in one injection. Combination insulin is used to simplify insulin regimens for people who require both types of insulin.

It is important to note that the type of insulin, dosage, and timing of injections will vary depending on each individual's unique needs and diabetes management plan. Therefore, people with diabetes need to work closely with their healthcare team to determine the most appropriate type of insulin and dosage regimen for them.

How is Insulin Administrated?

Insulin therapy can be administered in several ways, including injections, pens, and pumps. 

Subcutaneous injections

This is the most common method of insulin administration. Insulin is injected into the fatty tissue just under the skin using a syringe, pen, or pump. Subcutaneous injections are usually given in the abdomen, thighs, or upper arms.

Insulin pens

Insulin pens are pre-filled devices that contain insulin cartridges. They are easy to use and allow for more precise dosing than syringes. Insulin pens are available in both disposable and reusable forms.

Insulin Pumps

Insulin pumps are small, battery-operated devices that deliver a steady stream of insulin through a thin tube inserted under the skin. The pump is programmed to deliver a specific amount of insulin based on the user's blood sugar level, carbohydrate intake, and other factors.

Inhalable Insulin

Inhalable insulin is a newer form of insulin that is inhaled through the mouth. It is approved for use in certain adults with diabetes and is taken before meals.

The method of insulin administration may vary depending on individual needs, lifestyle, and treatment goals. 

How to Properly Store Insulin?

Insulin is a temperature-sensitive medication that should be stored properly to maintain its effectiveness. Here are some guidelines for storing insulin:

Refrigerate unopened insulin: Insulin should be stored in the refrigerator between 36°F and 46°F (2°C and 8°C) until it is opened. Do not freeze insulin or store it near the freezer compartment or in direct sunlight.

Room temperature storage: Opened insulin vials or pens can be stored at room temperature (between 59°F and 86°F or 15°C and 30°C) for up to 28 days. However, some insulin formulations require refrigeration even after opening, so it is important to read the manufacturer's instructions carefully.

Keep insulin away from heat: Insulin should not be exposed to extreme temperatures, such as in a hot car or near a heat source.

Protect insulin from light: Insulin should be kept in its original packaging to protect it from light exposure.

Check expiration date: Insulin has an expiration date, which should be checked before use. Expired insulin may not work properly and should be discarded.

Do not use damaged or discolored insulin: Insulin that is damaged or discolored should not be used and should be discarded.

It is important to follow these storage guidelines to ensure the safety and effectiveness of insulin therapy. If you have any questions or concerns about storing insulin, talk to your healthcare professional or pharmacist.

Side Effects of Insulin

Insulin is a safe and effective medication when used as directed by a healthcare professional. However, like any medication, insulin may cause side effects in some people. The most common side effects of insulin include:

1.) Hypoglycemia: Low blood sugar is the most common side effect of insulin. Symptoms may include sweating, shaking, weakness, hunger, dizziness, headache, blurred vision, irritability, and confusion.

2.) Allergic reactions: Some people may be allergic to insulin, which can cause symptoms such as hives, itching, rash, shortness of breath, and swelling of the face, tongue, or throat.

3.) Lipodystrophy: Repeated injections of insulin at the same site can cause changes in the fat under the skin, resulting in lumps or depressions in the skin.

4.) Weight gain: Insulin therapy may cause weight gain, especially if it is not used in combination with a healthy diet and exercise.

5.) Fluid retention: Insulin therapy may cause fluid retention, which can lead to swelling in the legs, ankles, or feet.

6.) Vision changes: Rapid changes in blood sugar levels can cause temporary changes in vision, such as blurred vision.

It is important to note that these side effects are generally mild and can be managed with proper diabetes management, medication adjustments, and lifestyle changes. 

If you experience any unusual symptoms or side effects while taking insulin, contact your healthcare provider immediately.