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An Overview of Sulfamethoxazole-Trimethaprim (Bactrim, Septra, Sulfatrim)

October 8, 2012

sul-fa-meth-OX-a-zole, trye-METH-oh-prim

Other Name(s): Bactrim, Bactrim DS, SMX-TMP, Septra, Sulfamethoprim, Sulfamethoprim-DS, Sulfatrim, TMP-SMX

What is sulfamethoxazole/trimethoprim?

Sulfamethoxazole/trimethoprim is an antibacterial prescription combination medicine approved by the U.S. Food and Drug Administration (FDA) to treat certain infections, such as:

Sulfamethoxazole/trimethoprim is also FDA-approved to prevent PCP in people who are immunosuppressed and are at risk of developing PCP.

Shigellosis and PCP are opportunistic infections. An opportunistic infection is an infection that occurs more frequently or is more severe in people with weakened immune systems -- such as those infected with HIV -- than in people with healthy immune systems.

Sulfamethoxazole/trimethoprim can also be used "off-label" to prevent and treat other opportunistic infections of HIV infection. "Off-label" use refers to use of an FDA-approved medicine in a manner different from that described on the medicine label. Good medical practice and the best interests of a patient sometimes require that a medicine be used "off-label."

What HIV-related opportunistic infections is sulfamethoxazole/trimethoprim used for?

The Guidelines for Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents, prepared by the U.S. Department of Health and Human Services (HHS) and the Centers for Disease Control and Prevention (CDC), includes recommendations on the HIV-related uses of sulfamethoxazole/trimethoprim to:

What should I tell my health care provider before taking sulfamethoxazole/trimethoprim?

Before taking sulfamethoxazole/trimethoprim, tell your health care provider:

Ask your health care provider about possible side effects from sulfamethoxazole/trimethoprim. Your health care provider will tell you what to do if you have side effects.

How should I take sulfamethoxazole/trimethoprim?

Take sulfamethoxazole/trimethoprim according to your health care provider’s instructions. Your health care provider will tell you how much sulfamethoxazole/trimethoprim to take and when to take it. Before you start sulfamethoxazole/trimethoprim and each time you get a refill, read any printed information that comes with your medicine.

How should sulfamethoxazole/trimethoprim be stored?

Where can I find more information about sulfamethoxazole/trimethoprim?

More information about sulfamethoxazole/trimethoprim is available:

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