Infusion Therapy: What It Is and What to Expect

Infusion therapy is a procedure in which medications are delivered directly into the bloodstream, usually with a needle and catheter that's inserted into a vein.

Infusion therapy is needed when a patient cannot take a drug orally. It's also a method of delivering medications in larger or more controlled amounts, such as during chemotherapy for cancer or with pain medication during childbirth.

You can get infusion therapy in a medical setting or at home. Insulin shots are an example of home infusion therapy.

This article explains the uses, benefits, and potential side effects of different kinds of infusion therapy.

Types of Infusion Therapy and Their Uses

The types of infusion therapy are:

• Intravenous (IV)
• Epidural
• Intramuscular
• Subcutaneous

Intravenous (IV)

Intravenous therapy is when medications or fluids are injected directly into the bloodstream. IV therapy is commonly used for:

• Maintaining fluids in the body after dehydration, diarrhea, vomiting, or surgery
• Chronic conditions, such as chemotherapy or immunotherapy for cancer
• Antibiotic therapy
• Administering anesthesia before surgery
• Blood transfusions
• Providing nutrients, like iron and B vitamins, when they are chronically low

Epidural

An epidural is a type of infusion therapy that is inserted around the spinal nerves in the lower back. Epidurals block pain signals from being sent from the spine to the brain. An epidural can administer the following:

• Analgesia (pain relief)
• Anesthesia (numbing)
• Steroids for pain, as with acute back pain

Epidurals are best-known as a way to prevent or numb the pain of childbirth, but they can also be used to prevent pain during and after surgery. Epidurals might also help relieve acute pain.

Intramuscular

Intramuscular infusion therapy is when medication is inserted into muscle tissue. Uses of intramuscular infusion therapy include:

• Hormone therapy, such as testosterone or estrogen injections for cancer treatment
• Antibiotics
• Vaccines
• Antibodies (immunoglobulins), which are proteins made by cells to help the immune system fight bacteria, viruses, or other harmful substances

Subcutaneous

Subcutaneous infusion therapy is when drugs are injected into fat underneath the skin. Subcutaneous injection sites include the upper arms, stomach, upper thighs, lower back and buttocks. Subcutaneous therapy includes:

• Insulin therapy for diabetics
• Opioids for pain relief
• Allergy medications like epinephrine
• Heparin, a medication used to prevent blood clots

Benefits of Infusion Therapy

The benefits of infusion therapy include:

• Fast-acting relief, especially in emergency situations, like after an allergic reaction or during childbirth
• Medication for those who cannot take pills orally
• Administering larger and/or controlled amounts of medication
• Intramuscular and subcutaneous injections help drugs remain in the body longer
• High success rates for several conditions

Side Effects of Infusion Therapy

Infusion therapy side effects might include:

• Redness at the site of injection
• Swelling
• Injury at the injection site
• Muscle pain
• Allergic reactions like rash, difficulty breathing, and confusion

The following are some risks associated with each type of infusion therapy.

IV Therapy Complications

IV therapy complications may include:

• Burning, stinging, or redness if IV solution leaks onto skin surrounding the injection site
• Pus leaking from injection if infected
• Pulmonary edema, or excess lung fluid: This requires quick medical attention and is marked by shortness of breath and coughing up a frothy substance.
• Air embolism (when air enters the vein): Symptoms include shortness of breath, increased heart rate, shoulder pain, light-headedness, and confusion.

Epidural Therapy Complications

Epidural therapy complications may include:

• Low blood pressure
• Headache
• Hot flashes
• Damaged blood vessel
• Damage to injection site nerves
• Losing bladder and bowel control

Intramuscular Therapy Complications

Intramuscular therapy complications may include:

• Nerve damage
• Medication leaking into surrounding tissue
• Muscle atrophy, or when a muscle loses strength
• Bone injury

Subcutaneous Therapy Complications

Subcutaneous therapy complications may include:

• Blister at injection site
• Headache
• Sore throat
• Nausea
• Kidney problems
• Blood clots

How to Prepare and What to Expect

To prepare for infusion therapy, you'll want to ask your practitioner about the following:

• If you have to avoid any foods or modify your medication schedule before treatment
• If others are allowed to come with you to the procedure
• If there will be pain and something to relieve that pain
• What will be used to treat allergic reactions if they arise
• How many sessions are required for treatment
• Any side effects you should monitor at home
• How many training sessions you and your caregivers will receive for home infusion therapy
• How to measure medications accurately for home infusion therapy

Expect the following during infusion therapy:

• That the injection site and needles are disinfected
• That the injection site is covered after your treatment
• Having a comfortable chair to sit in throughout the treatment
• Anesthesia for some larger needles that are used during treatment
• Being monitored throughout your therapy
• For home fusion, that you and your caregivers receive adequate training and follow-up appointments

Summary

Infusion therapy is when a medication or nutrient is inserted directly into a person's system. Infusion therapy can be intravenous (IV), meaning through an IV needle; an epidural, which is inserted around nerves in the spinal cord; intramuscular, which is inserted in muscle tissue; or subcutaneous, inserted into body fat under the skin.

A Word From Verywell

From vaccines to chemotherapy to monoclonal antibodies to treating COVID-19, infusion therapy has been a lifesaving treatment method for many. If being treated by a needle with powerful drugs sounds intimidating to you, express your concerns to your healthcare provider before the infusion therapy.

Also discuss side effects and potential complications and how to treat them. If you're getting home infusion therapy, be sure to ask for clear instructions and proper training beforehand. If you have a chronic illness, it's important to consider the different types of infusion therapy available to you, whether for pain relief, immunotherapy, or for rebalancing nutrients to prevent further disease.