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Compare Zithromax vs. Bactrim

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Azithromycin (Zithromax) and sulfamethoxazole/trimethoprim (Bactrim, Septra) are both antibiotics, but they belong to different classes and treat different types of infections. Azithromycin is a macrolide antibiotic taken once daily, typically for 3 to 5 days, and is used for infections like strep throat, sinus infections, and pneumonia. It works by stopping bacteria from making certain proteins. On the other hand, sulfamethoxazole/trimethoprim is a combination of a sulfonamide and an antifolate, taken twice daily, and is used for urinary tract infections, ear infections, and certain types of pneumonia. It works by stopping bacteria from making folic acid. Both are available as generic and come in tablet, liquid, and injectable forms. Azithromycin can cause side effects like diarrhea and stomach pain, whereas sulfamethoxazole/trimethoprim can cause nausea, rash, and increased sensitivity to sunlight. Both medications have serious side effects, but sulfamethoxazole/trimethoprim is not recommended during pregnancy and can cause low sodium and high potassium levels.

Azithromycin (Zithromax)
Sulfamethoxazole/trimethoprim
Azithromycin (Zithromax)
Sulfamethoxazole/trimethoprim
Summary of Zithromax vs. Bactrim
Summary for Macrolide antibiotic
Prescription only
Azithromycin (Zithromax) is a macrolide antibiotic. It's used to treat many types of infections in children and adults, including strep throat, sinus infection, and pneumonia. Azithromycin (Zithromax) is taken by mouth once daily. Typically, the length of treatment ranges from 3 to 5 days, depending on the type of infection you have. For convenience, azithromycin (Zithromax) also comes pre-packaged as Z-Pak. Some of the more common side effects of azithromycin (Zithromax) include diarrhea, stomach pain, and nausea.
Summary for Sulfonamide antibiotic
Prescription only
Sulfamethoxazole/trimethoprim (sometimes known as SMZ/TMP) is a combination medication containing an antifolate and sulfa antibiotic. It's used to treat different types of infections, such as urinary tract infections (UTIs), ear infections, and lung infections. This antibiotic has two different brand names, Bactrim and Septra, and it's also available as a lower-cost generic. It's a tablet that's taken by mouth, typically twice daily for most types of infections. This antibiotic also comes as a suspension under the brand name Sulfatrim for people who can't swallow tablets and as an injection for people in the hospital. Common side effects include nausea, diarrhea, and rash.
Indications of Zithromax vs. Bactrim
Indications for
Adults

Azithromycin (Zithromax) can treat certain types of:

•Sudden worsening of chronic obstructive pulmonary disease (COPD) from a bacterial infection

•Bronchitis

•Sinus infections

•Pneumonia

•Strep throat

•Tonsil infections

•Skin infections (e.g., cellulitis)

•Urethra or cervix infections

•Genital ulcer disease (chancroid)

Children

Azithromycin (Zithromax) can treat certain types of:

•Ear infections (ages 6 months and older)

•Pneumonia (ages 6 months and older)

•Strep throat (ages 2 years and older)

•Tonsil infections (ages 2 years and older)

Indications for

•Urinary tract infection (UTI)

•Lower respiratory tract infection (e.g., Pneumocystis pneumonia, infections related to bronchitis)

•Diarrhea caused by Shigella (shigellosis)

•Travelers' diarrhea - tablet or liquid only

•Ear infections - tablet or liquid only
Pros and Cons of Zithromax vs. Bactrim
Pros and Const for Macrolide antibiotic
Pros

•Taken by mouth once daily

•Treatment typically lasts only 3 to 5 days

•Comes as a liquid; good option for people who've trouble swallowing tablets

•Available as a lower-cost generic

Cons

•Might not be the best choice for people with severe liver problems or certain heart problems

•Can cause stomach-related side effects, like diarrhea and stomach pain

•Some bugs might be resistant to azithromycin (Zithromax)

Pros and Const for Sulfonamide antibiotic
Pros

•Treats many types of bacterial infections

•Can be given to children as young as 2 months old to treat certain infections

•Available as a lower-cost generic

Cons

•Can upset your stomach and make your skin more sensitive to the sun

•Not the best choice for people with liver or kidney problems

•Not recommended if you're pregnant

•Can't take if you have a sulfa allergy
Common Side Effects of Zithromax vs. Bactrim
Common Side Effects for
Adults

•Diarrhea (4-5%)

•Nausea (3%)

•Stomach pain (2-3%)

Children

•Diarrhea (2-6%)

•Vomiting (1-6%)

•Stomach pain (1-3%)

Common Side Effects for

•Nausea

•Vomiting

•Diarrhea

•Loss of appetite

•Rash

•Hives

•Skin sensitivity to sun or light
Warnings of Zithromax vs. Bactrim
Common Side Effects for

•Severe allergic and skin reactions

•Liver damage

•Heart rhythm problems (QT prolongation)

•Possible higher risk of death from heart problems

•Diarrhea from Clostridioides difficile infection

•Worsening of certain muscle problems (myasthenia gravis)

•Doesn't treat syphilis

Common Side Effects for

•Not for use during pregnancy

•Severe allergic reactions and skin reactions

•Low platelet counts and risk for bleeding

•Diarrhea from Clostridioides difficile infection

•Low sodium levels and high potassium levels

•Blood cell-related problems

•Problems with processing phenylalanine - for people with phenylketonuria (PKU) only
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Compare Zithromax vs. Bactrim

Key takeaways

Summary of Zithromax vs. Bactrim

Indications of Zithromax vs. Bactrim

Pros and Cons of Zithromax vs. Bactrim

Common Side Effects of Zithromax vs. Bactrim

Warnings of Zithromax vs. Bactrim

Prices with our coupons for Zithromax vs. Bactrim

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