Co-trimoxazole
Sulfamethoxazole · Trimethoprim
Co-trimoxazole tablets combine sulfamethoxazole with trimethoprim, in 400/80mg and 800/160mg strengths, for urinary tract infections and other bacterial illness.
All strengths and pack prices
| Strength | Pack | Price | Per tablet |
|---|---|---|---|
| 400/80mg | 30 tablets | $23.70 | $0.79 |
| 400/80mg | 60 tablets | $42.00 | $0.70 |
| 400/80mg | 90 tablets | $55.80 | $0.62 |
| 400/80mg | 120 tablets | $64.80 | $0.54 |
| 400/80mg | 180 tablets | $84.60 | $0.47 |
| 400/80mg | 360 tablets | $140.40 | $0.39 |
| 800/160mg | 30 tablets | $27.30 | $0.91 |
| 800/160mg | 60 tablets | $46.80 | $0.78 |
| 800/160mg | 90 tablets | $63.90 | $0.71 |
| 800/160mg | 120 tablets | $74.40 | $0.62 |
| 800/160mg | 180 tablets | $97.20 | $0.54 |
| 800/160mg | 360 tablets | $169.20 | $0.47 |
- Category
- Antibiotics
- Active ingredient
- Sulfamethoxazole · Trimethoprim
- Route
- Oral
- Form
- Tablet
- Strengths
- 400/80/800/160mg
You will receive a quality generic, depending on stock.
Shipped in a discreet, unmarked envelope.
Details
- Conditions
- Urinary tract infections
- Therapeutic Class
- Sulfonamide Antibiotic
- Pharmacological Class
- Antibiotic
- Minor Side Effects
- Nausea, Vomiting
- Moderate Side Effects
- Itching, Mild rash
- Dosage Forms
- Tablet
- Administration Route
- Oral
- Originator
- GSK
- Onset Time
- 1–2 hours
- Duration
- 12 hours
- Storage Instructions
- Store in a cool, dry place.
- Drug Interactions
- Methotrexate, Digoxin
- Age Restrictions
- Not for babies under 6 weeks old
What you will receive
Co-trimoxazole is a generic medicine sold under the name of its active ingredient, Sulfamethoxazole / Trimethoprim.
- The manufacturer depends on what is in stock when your order ships.
- It contains the same active ingredient, at the same strength, as the brand-name versions.
FAQ
Which Co-trimoxazole strengths and pack sizes can I order?
These co-trimoxazole tablets (sulfamethoxazole with trimethoprim) come as 400/80mg and 800/160mg. Packs hold 30, 60, 90, 120, 180 or 360 tablets. Larger packs cost less per tablet.
What happens if my Co-trimoxazole parcel goes missing?
If a Co-trimoxazole parcel does not arrive within the delivery window, it is sent again free. If that is not possible, the order is refunded. Tracked courier takes 5 to 9 business days with online tracking; standard airmail takes 14 to 21 business days and is untracked.
What are the brand names for sulfamethoxazole and trimethoprim?
Brand names for sulfamethoxazole and trimethoprim include Bactrim, Septra and Septrin. Co-trimoxazole tablets are a pure generic sulfamethoxazole and trimethoprim product and are not any of those brands. Here, sulfamethoxazole and trimethoprim can also be bought online as generic Bactrim.
What is the difference between the 400/80mg and 800/160mg tablets?
The 800/160mg tablet holds twice as much of each antibiotic as the 400/80mg one, in the same five-to-one ratio, so it is usually taken fewer times a day. Both treat the same infections; which one suits a course is a matter of dose, not of strength of effect.
How long does it take for a urinary tract infection to improve?
Usually the burning and the constant urge start easing within the first few days. Easing is not the same as clearing: some bacteria remain in smaller numbers, and they are the ones that return if the course is cut short, which is why the tablets are taken through to the last day.
Can I take these tablets if I am allergic to sulfa drugs?
Sulfamethoxazole belongs to the sulfonamide family, so a previous reaction to a sulfa antibiotic — rash, swelling or breathing trouble — rules this combination out. Trimethoprim by itself is a different medicine and is not a sulfonamide.
Does co-trimoxazole make your skin sensitive to the sun?
Yes. It can make skin burn more easily, so cover up, use sunscreen and stay out of strong midday sun while you are taking the tablets. The sensitivity usually settles once the course ends.
Can I take co-trimoxazole for a cold or a sore throat?
No. Colds, flu and most sore throats are caused by viruses, and co-trimoxazole only stops bacteria, so it will not shorten a viral illness or ease its symptoms. Keeping it for infections that bacteria are actually causing also helps it go on working when it is needed.
About Co-trimoxazole
What co-trimoxazole tablets contain
Co-trimoxazole is the name for a pair of antibiotics: sulfamethoxazole 400mg with trimethoprim 80mg, or the double-strength 800/160mg. Some pharmacies label it by one ingredient only, as trimethoprim tablets, but these two strengths always mean the pair. Together they block two steps of the same pathway that bacteria use to make folate, the material the germs need to build DNA and multiply. Neither drug does that job as well alone.
Bactrim is the same combination in the same two strengths under a brand name. The two antibiotics are described on the sulfamethoxazole and trimethoprim pages.
What the tablets are used for
Bacterial infections, most often of the urinary tract — the burning or stinging when you pass urine, the constant need to go, the heavy feeling low in the belly. Co-trimoxazole also treats travellers' diarrhoea and some chest, skin and ear infections. It is no use against colds, flu or other viral illness.
You should start to feel better in the first few days. Keep taking the tablets to the end of the course all the same: the bacteria that survive a half-finished course are the ones that come back resistant.
Fitting the doses into your day
Courses run from a few days to a couple of weeks, and most are taken two to four times a day. Space them evenly and keep to roughly the same times — with breakfast and your evening meal, for instance. Food makes no difference to how well they work, so take them with a meal if they leave you queasy. Drink plenty of water through the day. If you forget a dose, take it late rather than skipping it, but do not double up at the next one.
Side effects and what needs urgent help
A queasy stomach, nausea, vomiting and going off your food are the usual complaints, and they settle. A sore mouth or a mild rash can also turn up.
Get help straight away for a rash that spreads, itches, blisters or peels; swelling of the face, lips or throat; fever with chills; breathlessness or a new cough; unexplained bruising or bleeding; or red and purple patches on the skin. Severe diarrhoea, watery or bloody, sometimes with cramps, can start during the course or as long as two months after it and needs urgent treatment too.
Who should not take it, and what it interacts with
Two groups are ruled out: anyone allergic to sulfonamide (sulfa) drugs, since sulfamethoxazole belongs to that family, and babies under six weeks old. On the medicine side, potassium is the thing to watch. Co-trimoxazole can push it up, so it adds to potassium-sparing diuretics such as spironolactone or amiloride, and to ACE inhibitors or ARBs taken for blood pressure. Warfarin and similar blood thinners also act more strongly alongside it, which means easier bruising and bleeding.
Sources
- Co-trimoxazole: MedlinePlus Drug Information — National Library of Medicine
- CDC - Antibiotic Use — CDC