Bactrim Tablet: Uses, Dosage, Side Effects, Precautions and Alternates

Quick overview

Bactrim Tablet is a combination antibiotic containing sulfamethoxazole and trimethoprim, from the sulfonamide drug class. It is used to treat infections such as urinary tract infections, ear infections, chronic bronchitis flare-ups, and Pneumocystis jirovecii pneumonia, among others. The two active ingredients work together to stop bacteria from growing and kill them. It should be taken exactly as prescribed, with attention to important warnings around pregnancy, kidney and liver function, and skin reactions.

What is Bactrim Tablet

Bactrim is a combination antibiotic made of two medicines, sulfamethoxazole and trimethoprim, that work together to fight bacterial infections.

Bactrim Tablet uses

• Urinary tract infections
• Ear infections (acute otitis media) in children
• Flare-ups of chronic bronchitis in adults
• Traveler's diarrhea caused by certain E. coli strains
• Shigellosis (a type of bacterial dysentery)
• Prevention and treatment of Pneumocystis jirovecii pneumonia, especially in people with weakened immune systems
• Typhoid and paratyphoid fever

Benefits of Bactrim Tablet

• Treats infections caused by susceptible bacteria in the urinary tract, prostate, and respiratory system
• Can be used both to treat and to prevent Pneumocystis jirovecii pneumonia in people with weak immune systems

How Bactrim Tablet works

The two active ingredients block two different steps that bacteria need to make essential building blocks, which stops the bacteria from growing and kills them.

Bactrim Tablet dosage

Take this medicine exactly as your doctor tells you; do not change the dose or stop treatment early without talking to your doctor. Drink plenty of water while taking this medicine to help prevent kidney stones and crystals forming in your urine. Keep taking this medicine for the full course even if you start to feel better, to avoid the infection coming back or becoming resistant to treatment. If you forget a dose, do not take a double dose to make up for it. This medicine should not be given to children under 6 weeks of age (leaflet) or under 2 months of age (prescribing information). The tablet may be split into two equal halves if needed.

Available forms and strengths

• Tablets
• Double strength (DS/forte) tablets
• Double strength tablet strength: 800/160 mg

Side effects of Bactrim Tablet

Common

• Nausea
• Vomiting
• Loss of appetite
• Skin rash
• Elevated liver values seen in blood tests
• Elevated kidney values seen in blood tests
• Skin inflammation and redness
• Itching

Serious

• Severe allergic reaction with swelling of the face, tongue, or throat, difficulty swallowing, or hives with breathing difficulty
• Severe skin reactions such as Stevens-Johnson syndrome, toxic epidermal necrolysis, DRESS, or AGEP, which can cause skin blistering and peeling
• Signs of low white blood cells such as fever with sore throat, mouth ulcers, or urinary problems
• Unexplained muscle pain, cramps, or weakness (possible muscle breakdown)
• Severe or bloody diarrhea, which could signal a serious bowel infection
• Yellowing of the skin or eyes (possible liver problems)
• Unusual bruising or bleeding, pale skin, or feeling very tired (possible blood cell problems)
• Seizures
• High potassium levels causing nausea, weakness, tingling, chest pain, or irregular heartbeat
• Low sodium levels causing headache, confusion, weakness, or feeling unsteady
• New or worsening cough and shortness of breath
• Severe immune reaction causing fever, swollen glands, tiredness, dizziness, shortness of breath, bruising, or rash together

Warnings and precautions

• Stop the medicine and get medical help right away if you notice a rash, blistering, or skin peeling, as this could be a serious skin reaction.
• If you have had a serious skin reaction to this medicine before, you should never take it again.
• This medicine must not be taken together with dofetilide, a medicine used for heart rhythm problems.
• People over 65, or who are malnourished or severely dehydrated, should talk to their doctor before starting this medicine because of higher risk of side effects.
• This medicine may increase the risk of birth defects if used during pregnancy, particularly affecting the brain, spine, heart, urinary tract, mouth, or feet of the developing baby.
• This medicine can make your skin more sensitive to sunlight, so protect your skin when outdoors.
• This medicine should not be used during pregnancy unless a doctor has said it is necessary, because it may affect the unborn baby.
• This medicine should not be used while breastfeeding unless a doctor has said it is necessary, because it passes into breast milk.
• People with kidney problems should ask their doctor for advice before starting this medicine, and this medicine must not be used if kidney function is severely reduced.
• This medicine must not be used if you have severe liver damage.
• This medicine is not expected to affect your ability to drive or use machines, although no formal studies have been done.

Storage

• Keep this medicine out of the sight and reach of children.
• Do not use this medicine after the expiry date which is stated on the carton. The expiry date refers to the last day of that month.
• Bactrim/Bactrim forte must be stored in the original package.
• Do not throw away this medicine via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use.
• Store at 20° to 25°C (68° to 77°F).

When to see a doctor

• Get emergency help if you notice swelling of the face, tongue, or throat, trouble swallowing, or hives with breathing problems.
• Contact your doctor immediately if you suddenly develop a worse cough and shortness of breath.
• See a doctor as soon as possible if you develop fever with a very poor general feeling, or fever with a sore throat, mouth, or urinary symptoms, since this could mean a drop in white blood cells.
• Contact your doctor right away if you develop unexplained muscle pain, cramps, or weakness.
• Contact your doctor if you develop watery or bloody diarrhea, even if it happens weeks after finishing the medicine.
• If you develop fever, swollen glands, tiredness, dizziness, shortness of breath, bruising, or a rash together, contact a doctor immediately as this may be a rare but life-threatening immune reaction.

Alternatives

• Septra
• Septra DS
• SMZ-TMP DS
• Cotrim
• Co-trimoxazole
• Sulfatrim