The Z-track method is an intramuscular injection (IM) technique used to ensure the medication stays in the muscle instead of leaking into the surrounding tissue.
Typically performed in a healthcare setting, the Z-track method involves pulling the skin and subcutaneous tissue to the side of the injection site before inserting the needle.
Once the needle is removed, the tissue is released. This creates a zigzag pattern or Z track of the needle path. As a result, the medication is less likely to track (leak) back through the site into the surrounding tissue.
This article explains the Z-track method of injection. It provides step-by-step instructions for how to use the Z-track method and why it may be used.
Purpose of the Z-Track Method
The idea behind the Z-track method of IM injections is to put medications into the muscle tissue and not allow them to leak (track) back into the subcutaneous tissue layer over the muscle.
Medication absorption in the muscle is different than in the subcutaneous tissue, so it is important that medications designed to be absorbed through the muscle stay in the muscle.
The the Z-track method is only used is for intramuscular injections, and not other types of injections. The type and amount of medication given will help determine the length and gauge of the needle as well as the proper location of the injection.
Patients who are learning to give injections for home-based treatment should ask their healthcare provider to explain the best method for their specific medication and situation.
How the Z-Track Method Works
The track is the path that a needle makes through skin, fat, and muscle tissue when giving an injection. Any kind of injection creates a track from the needle site. When the needle is removed, a small amount of medication or blood—can sometimes wick up through the track and leak out of the body. That leaking is also called tracking.
The Z-track method helps to prevent leaking after an IM injection by altering the track created by the needle. When done properly, there are two curves in the track that gives it the "Z" shape. You can't see the track because it's under the skin, but you may know that it was effective if no medication leaks out after the injection.
In addition to helping to prevent leaking, there is some question over whether using the Z-track method reduces pain when giving an intramuscular injection.
Risks and Contraindications
There are no known risks or contraindications for using the Z track method for intramuscular injections, however it is important to note that this can be performed only for intramuscular injections.
The Z track method will not be appropriate for any types of medications that are given via subcutaneous injection or intravascularly. Your healthcare provider will advise you on which medications can be used with this method.
Before the Injection
For patients, caregivers, or family members who are administering medications at home, be sure to ask a healthcare provider to instruct on the proper technique for administering an intramuscular injection. You should feel confident administering the injection prior to performing it.
Equipment
Proper equipment for performing an intramuscular injection includes:
- Proper size syringe and hypodermic needle
- Clean exam gloves
- Alcohol swab
- Adhesive bandage
The size of the syringe is based on the amount of medication given as measured in milliliters (ml) or cubic centimeters (cc). A milliliter is the same as a cubic centimeter and volume can be expressed using either measurement.
The smallest syringe available for the volume of liquid administered is best for proper control and dosing. For example, to administer .5 ml of medication, it is best to use a 1 cc syringe. To administer 2 ml of liquid, it is usually best to use a 3 cc syringe.
Using the appropriate size syringe can help minimize the risk of medication errors. Using a 10 ml syringe for an injection of less than 3 ml of medication could result in accidentally drawing up too much or too little medication.
The size of the needle is expressed in both length and gauge (diameter). The lower the gauge number, the larger the diameter of the needle.
For example, a 22 gauge needle is smaller than an 18 gauge needle. Thicker and more viscous medications require a larger gauge needle.
The length of a needle is expressed in centimeters (cm) or inches. Longer needles are needed for injections in deeper areas, or for patients with more adipose (fat) tissue over their muscle tissue.
Preparing for the Injection
Once all of the equipment is gathered, the caregiver should wash his or her hands thoroughly for at least 60 seconds. Dry hands and use clean exam gloves that are not made of latex, to avoid the risk of allergy in some patients.
Timing
It shouldn't take more than a minute or two to perform an injection. Using the Z-track method does not add any appreciable time to the process of an intramuscular injection.
Injection Sites
The patient's healthcare provider or caregiver should determine the proper injection site based on the volume and type of medication being administered, the patient's age, the patient's size, and past medical or surgical history.
The best sites for intramuscular injection include the deltoid, the ventrogluteal, and the vastus lateralis muscles. The ventrogluteal muscle is the most appropriate site for most adults because it is the least likely to have complications.
There are fewer limitations in the volume of the IM medication administered at this site. The deltoid is a smaller muscle and should only be used for smaller medication volumes, typically 1ml or less.
Prepare the Medication
Follow the instructions provided by the healthcare provider or caregiver for preparing the medication. Some medications are provided ready for injection directly out of the vial.
Other medications require mixing of either two or more liquids, or by reconstituting a dry powder into a liquid solution. If preparing the medication, make sure to double check medications and dosages to follow the instructions exactly.
Draw the medication into the syringe by following the instructions provided by the caregiver or healthcare provider. Make sure there is no air in the syringe that can be injected into the patient. Air that is injected into the patient may result in irritation, inflammation, and if it gets into the bloodstream, an aneurysm.
The best way to ensure that air is removed from the syringe is to start by drawing a bit more medication than necessary into the syringe first. It's okay if a small amount of air is in the syringe at this point.
Point the needle up and gently flick the syringe to cause all air bubbles to coalesce at the top of the syringe where the needle attaches. Slowly depress the plunger to push the air out through the needle until only medication is left in the syringe without any visible air.
Continue to push until only the correct amount of medication remains in the syringe and a drop of medication is visible at the tip of the syringe.
Prepare the Injection Site
Using the alcohol swab, wipe clean the skin on site of the injection in progressively larger concentric circles, moving away from the site at the center. If additional cleaning is necessary, perform that first and make the alcohol swab the final preparation.
If needed, an iodine solution may be used to help clean the site prior to using the alcohol swab. Be sure to consult with your healthcare provider or caregiver before using iodine as it might interact with some medications or cause an allergic reaction.
How To Give a Z-Track Injection
To perform the injection using the Z track method, follow these steps:
- Gently but firmly use your non-dominant hand to pull the skin in one direction away from the site of the injection.
- With the exact amount of prepared medication already drawn into a syringe, insert the needle into the injection site at a 90-degree angle to the skin, while continuing to hold the skin with your other hand. Your healthcare provider will tell you how deep to insert the needle.
- Slowly and gently depress the plunger of the syringe to inject the medication into the patient's muscle. Make sure you do not push needle in further while you are pushing the plunger. Continue to hold the skin with your other hand.
- Once the syringe is empty, remove the needle by pulling the entire syringe straight out of the muscle in the same angle that it was inserted.
- Now release the skin to allow it to return to its original position. Performing an IM injection with this method can allow the pulled skin and soft tissue to cover the track once it is released and can prevent leaking.
Throughout the Procedure
It is important for the patient not to move during the injection. Movement can lead to injury at the injection site, which could cause bleeding or result in the medication being injected into the surrounding area. If enters the bloodstream, it could cause abnormally rapid absorption of the medication.
Some providers will pull back on the plunger after the needle is inserted and before the medication is given. This is to ensure that the medication was not being injected directly into a vein.
However, this is not tyically needed for intramuscular injections and in some cases can increase the chance of irritation or damage to the surrounding tissues.
Post-Procedure
Do not rub the site after the injection. That can force medication to leak out of the injection site.
After the Injection
Once you have completed an intramuscular injection using the Z-track method, cover the site of the injection with an adhesive bandage. Keep any injection site clean and covered.
Look for signs of irritation or infection such as swelling, an injection site that is hot to the touch, and redness. If any signs of irritation are noted, be sure to contact your healthcare provider for guidance.
A Word From Verywell
This guide is intended to be a reference and to support the instruction you received from your healthcare provider. It is not intended to replace any instruction you may have received.
The Z-track method is a useful technique for administering intramuscular injections with as little leaking as possible, but the safety and success of an injection relies on adherence to general protocols surrounding the injection.
Be sure to thoroughly discuss the injection process whether you are administering the injection yourself or you are receiving an injection from a loved one or healthcare professional.
