Introduction

Sulfamethoxazole (sul-fa-meth-OX-a-zole)

Treats urinary tract infections, ear infections, and other general infections caused by bacteria. May also be given in combination with other medicines. Belongs to a class of drugs called sulfonamides (sulfa drugs).

Brand Name(s)

There may be other brand names for this medicine.

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to sulfamethoxazole or to any other sulfa drug. You should not use this medicine if you will soon be having a baby or if you are breastfeeding.

How to Use This Medicine

Tablet

• Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
• Drink plenty of water while using this medicine.
• Use this medicine for the full time of treatment, even if you begin to feel better. If you stop using this medicine too soon, your infection may come back.

If a dose is missed:

• Use your medicine as soon as possible unless it is almost time for your next dose.
• Skip the missed dose if it is almost time for your next regular dose.
• Do not use two doses at the same time.

How to Store and Dispose of This Medicine

• Store at room temperature in a closed container, away from heat, moisture, and direct light.
• Keep this and all medicine out of the reach of children.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Make sure your doctor knows if you are also using Coumadin®, Dilantin®, or methotrexate.

Warnings While Using This Medicine

• If you are pregnant or breastfeeding, talk to your doctor before using this medicine.
• Make sure your doctor knows if you have kidney or liver disease, asthma, or G6PD (glucose-6-phosphate dehydrogenase) deficiency.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

• Fainting
• Fast or irregular heartbeat
• Fever
• Muscles aches
• Rash, blistering, or purple spots on the skin
• Shortness of breath
• Skin rash, hives, or itching
• Sore throat or cough
• Swelling in face, throat, or lips
• Wheezing or trouble breathing
• Yellow eyes or yellow or pale skin

If you notice these less serious side effects, talk with your doctor:

• Headache
• Nausea, vomiting, or diarrhea