What antibiotic shot is given in the buttocks?

October 9, 2025 •

4 min read

Globally, over 16 billion injections are administered annually [1.9.5]. A common question among patients is, 'What antibiotic shot is given in the buttocks?' This method is crucial for delivering specific medications effectively.

Quick Summary

Antibiotic shots in the buttocks, or intramuscular (IM) gluteal injections, are common for drugs like Penicillin G and Ceftriaxone. This site is chosen for its large muscle mass, which can handle larger volumes and more irritating medications [1.5.3].

Key Points

Primary Antibiotics: Penicillin G (Bicillin L-A) and Ceftriaxone (Rocephin) are common antibiotic shots given in the buttocks [1.2.1, 1.2.5].
Gluteal Muscle Advantage: The buttocks' large gluteal muscle is chosen because it can absorb larger volumes of medication and is less sensitive to irritating drugs [1.5.3, 1.5.5].
Key Conditions Treated: These injections are used for serious bacterial infections like syphilis, gonorrhea, pelvic inflammatory disease, and strep throat [1.6.1, 1.6.2].
Injection Sites: The ventrogluteal site (on the hip) is preferred as the safest location, while the dorsogluteal site requires caution to avoid the sciatic nerve [1.9.1, 1.7.4].
Z-Track Method: This technique is often used to prevent medication from leaking into subcutaneous tissue, reducing irritation and ensuring the full dose is delivered to the muscle [1.8.4].
Common Side Effects: Pain, swelling, and redness at the injection site are common; applying a warm or cold compress can help alleviate discomfort [1.2.1, 1.2.2].
Professional Administration: Antibiotic injections must be administered by a healthcare professional to ensure correct placement and minimize risks [1.3.1, 1.5.4].

Introduction to Intramuscular Antibiotic Injections

When a bacterial infection requires rapid treatment or when oral medications are not suitable, a doctor may prescribe an intramuscular (IM) antibiotic injection [1.6.4]. The buttocks, specifically the gluteal muscles, are a frequent site for these shots. This is not a random choice; the gluteal muscles are large and have a good blood supply, which allows them to absorb larger volumes of medication and drugs that might be irritating to smaller muscles [1.5.3, 1.5.5]. This article explores the common antibiotics administered this way, the reasons behind this method, and what patients can expect.

Why the Buttocks? The Rationale Behind Gluteal Injections

The primary reason for using the gluteal muscles for an antibiotic shot is their size and capacity. Muscles in the buttocks can absorb a larger volume of medication (up to 4 mL) compared to smaller muscles like the deltoid in the arm (which can typically only handle up to 2 mL) [1.5.1, 1.9.1]. This is important for antibiotics that are viscous (thick) or require a larger dose.

Additionally, muscle tissue is less sensitive than subcutaneous tissue, making it a better choice for potentially irritating medications [1.5.2]. The rich blood supply ensures the antibiotic is absorbed efficiently into the bloodstream to fight the infection [1.5.3].

There are two main sites within the gluteal region used for injections:

Ventrogluteal site: Located on the side of the hip, this is considered the safest and preferred site for adults and children. It is free of major nerves and blood vessels [1.9.1, 1.5.6].
Dorsogluteal site: This is the upper-outer quadrant of the buttock. While traditionally common, it is used with more caution today due to the risk of injuring the sciatic nerve if the injection is not administered correctly [1.7.4, 1.9.1].

Common Antibiotics Given via Gluteal Injection

Two of the most well-known antibiotics given as a shot in the buttocks are from the penicillin and cephalosporin families.

Penicillin G Benzathine (Bicillin L-A)

Penicillin G benzathine is a long-acting form of penicillin that is given deep into the buttock muscle [1.2.1, 1.2.2]. It works by killing bacteria and is used to treat a variety of serious bacterial infections [1.3.2]. A key use for this injection is the treatment of syphilis; often a single dose is sufficient for early-stage infections [1.2.2, 1.3.5]. It is also used to treat and prevent other infections like strep throat and rheumatic fever [1.6.1, 1.6.3]. Because it is a thick suspension, the large gluteal muscle is an ideal site for this injection [1.3.3].

Ceftriaxone (Rocephin)

Ceftriaxone is a broad-spectrum cephalosporin antibiotic used to treat numerous bacterial infections, including gonorrhea, pelvic inflammatory disease (PID), meningitis, and infections of the lungs, skin, and urinary tract [1.2.6, 1.6.2]. While it can be given intravenously (IV), it is also commonly administered as an IM injection in a large muscle like the gluteus [1.2.5, 1.4.5]. For treating uncomplicated gonorrhea, a single 500 mg IM dose is often recommended [1.4.2]. The injection can be painful, so it is sometimes mixed with a local anesthetic like lidocaine to reduce discomfort [1.4.2, 1.4.3].

Comparison of Common IM Antibiotics


Feature	Penicillin G Benzathine (Bicillin L-A)	Ceftriaxone (Rocephin)
Antibiotic Class	Penicillin [1.2.1]	Cephalosporin [1.2.6]
Common Uses	Syphilis, strep throat, rheumatic fever prevention [1.6.1, 1.6.3]	Gonorrhea, PID, meningitis, various infections [1.6.2]
Administration	Deep IM injection, often as a single or limited series of doses [1.2.1, 1.3.2]	IM or IV injection; can be a single dose or multiple doses [1.2.5, 1.6.2]
Common Side Effects	Injection site pain, nausea, vomiting, diarrhea [1.2.1]	Injection site pain, diarrhea, stomach pain, rash [1.4.3, 1.7.1]
Key Consideration	Must not be injected into a vein [1.2.1, 1.7.5]. A potential for severe allergic reactions in those allergic to penicillin [1.3.2].	Can be mixed with lidocaine to reduce pain [1.4.2]. Patients allergic to penicillin may also be allergic to cephalosporins [1.4.3].

The Injection Procedure and What to Expect

A healthcare professional will always administer an antibiotic shot. They are trained to identify the correct injection site to avoid nerves and blood vessels [1.5.4].

To minimize medication leakage and skin irritation, a technique called the Z-track method is often recommended for IM injections [1.8.4]. This involves the nurse or doctor pulling the skin and subcutaneous tissue to the side before inserting the needle. After the medication is injected, the skin is released. This creates a zigzag path that seals the medication within the muscle, preventing it from leaking out [1.8.1, 1.8.5].

Pain at the injection site is a common and expected side effect [1.2.2]. The discomfort can range from mild to severe and may last for a few days. Applying a warm compress or ice pack can help soothe the area [1.2.2]. Other potential side effects include swelling, redness, or a lump at the injection site [1.2.1]. While rare, more serious complications can include nerve damage or an abscess [1.7.4].

Conclusion

The antibiotic shot given in the buttocks is typically a powerful medication like Penicillin G or Ceftriaxone, used to treat serious bacterial infections. The gluteal muscle is selected for its size and vascularity, which allow for safe and effective absorption of large or irritating medications [1.5.3, 1.5.5]. While the injection can be painful, proper administration techniques like the Z-track method help minimize discomfort and complications [1.8.4]. As with any medical procedure, it is vital that these injections are given by a qualified healthcare professional.

For more information, you can consult MedlinePlus, a service of the National Library of Medicine. MedlinePlus [1.2.1]

Frequently Asked Questions

The most common are Penicillin G benzathine (Bicillin L-A) and Ceftriaxone (Rocephin). They are used to treat various bacterial infections, including STIs like syphilis and gonorrhea [1.2.1, 1.6.2].

The buttock has larger muscles (gluteal muscles) that can accommodate a greater volume of medication and are better for drugs that may be thick or irritating. The arm's deltoid muscle is smaller and can only handle small volumes [1.5.3, 1.5.5].

Pain at the injection site is a common side effect. The level of pain varies depending on the medication's thickness and the individual. For example, Ceftriaxone shots are known to be painful and are often mixed with lidocaine to reduce discomfort [1.4.2, 1.2.2].

The Z-track method is an injection technique where the skin is pulled to the side before the needle is inserted. This creates a zigzag path when the skin is released, which seals the medication inside the muscle and prevents it from leaking out, reducing irritation [1.8.5].

A Penicillin G shot (Bicillin L-A) is the preferred treatment for all stages of syphilis [1.3.5]. It is also used for other bacterial infections like strep throat and to prevent conditions such as rheumatic fever [1.6.1, 1.6.3].

No. Antibiotics like penicillin and ceftriaxone are only effective against bacterial infections. They will not work for viral infections such as the common cold or influenza (flu) [1.2.1, 1.6.2].

Common risks include pain, swelling, and bruising at the injection site [1.2.1]. More serious but rare risks include damage to the sciatic nerve (especially with the dorsogluteal site), abscesses, and allergic reactions [1.7.4].