Generic Bactrim DS – Product Description for EZ Chemist Online Pharmacy

What is Generic Bactrim DS used for?
Generic Bactrim DS is a combination antibiotic containing sulfamethoxazole and trimethoprim. It is used to treat a wide range of bacterial infections such as urinary tract infections (UTIs), bronchitis, traveler’s diarrhea, ear infections, and Pneumocystis jirovecii pneumonia (PCP). Available at EZ Chemist, this double-strength formulation provides potent antimicrobial coverage through dual inhibition of bacterial synthesis pathways.

Product Name:
Generic Bactrim DS (Double Strength Tablets)

Active Ingredients:
Sulfamethoxazole 800 mg

Trimethoprim 160 mg

Other Popular or Common Names:
Cotrimoxazole

SMX-TMP

TMP-SMX

Sulfamethoxazole/Trimethoprim DS

Septra DS (Brand)

Bactrim DS (Brand)

Mode of Action:
Generic Bactrim DS acts through synergistic inhibition of two consecutive steps in bacterial folic acid synthesis:

Sulfamethoxazole inhibits dihydropteroate synthase, preventing the formation of dihydrofolic acid.

Trimethoprim inhibits dihydrofolate reductase, blocking the conversion of dihydrofolic acid to tetrahydrofolic acid.

This dual action makes the drug bactericidal against a broad range of Gram-positive and Gram-negative bacteria.

Therapeutic Uses:
Generic Bactrim DS is used in the treatment of:

Urinary Tract Infections (UTIs)

Acute and chronic bronchitis

Otitis media (middle ear infections)

Traveler’s diarrhea

Shigellosis

Pneumocystis jirovecii pneumonia (PCP) – treatment and prophylaxis

Nocardiosis

Toxoplasmosis (off-label)

Dosage & Administration:
Adults and Adolescents (≥12 years):

Standard Dose: One tablet (800 mg/160 mg) every 12 hours for 10–14 days, depending on infection type.

Pediatric Dosing:

Dosage is weight-based and should be calculated by a healthcare provider.

PCP Treatment:

15–20 mg/kg/day of trimethoprim component in divided doses every 6–8 hours for 14–21 days.

Administration Tips:

Take with a full glass of water.

Can be taken with or without food, though food may reduce stomach upset.

Complete full course even if symptoms resolve early.

Prescribing Information:
Prescription required.

Avoid use in infants under 2 months of age.

Renal function must be monitored; dose adjustment may be required.

Perform regular complete blood count (CBC) during prolonged therapy.

Contraindicated in folate-deficient patients and those with sulfonamide allergy.

Drug Classification:
Therapeutic Class: Antibiotic

Pharmacologic Class: Sulfonamide and folate synthesis inhibitor combination

Schedule: Prescription-only medicine (Rx)

Safety Information:
Contraindications:
Known hypersensitivity to sulfonamides or trimethoprim

Megaloblastic anemia due to folate deficiency

Severe renal or hepatic dysfunction

Pregnancy (particularly in the first trimester and near term)

Infants under 2 months

Precautions and Warnings:
Risk of Stevens-Johnson Syndrome and toxic epidermal necrolysis

May cause blood dyscrasias including agranulocytosis, aplastic anemia

Use with caution in elderly patients and those with renal impairment

Monitor potassium levels; may cause hyperkalemia

Potential photosensitivity; use sun protection

Avoid in patients with G6PD deficiency due to risk of hemolysis

Pregnancy & Lactation:
Category D (Trimethoprim may interfere with folate metabolism)

Not recommended during breastfeeding unless benefits outweigh risks

Possible Side Effects:
Common:

Nausea, vomiting

Rash

Loss of appetite

Serious (Seek immediate medical attention):

Skin reactions (e.g., SJS, TEN)

Liver toxicity

Blood cell disorders (e.g., leukopenia, thrombocytopenia)

Hyperkalemia

Crystalluria

Drug Interactions:
Generic Bactrim DS interacts with several drugs. Clinically significant interactions include:

Drug Effect Notes
Warfarin Increased bleeding risk Monitor INR closely
ACE inhibitors / ARBs / Potassium-sparing diuretics Hyperkalemia Monitor serum potassium
Methotrexate Increased toxicity Avoid combination
Phenytoin Increased phenytoin levels Monitor serum levels
Cyclosporine Nephrotoxicity risk Avoid if possible
Oral contraceptives Reduced effectiveness Use backup contraception

Clinical Study Reference: A systematic review in Clinical Infectious Diseases (CID) confirms increased risk of adverse renal and hematologic effects when combined with methotrexate and ACE inhibitors.

Frequently Asked Questions (FAQs)
Q1: Can I buy Generic Bactrim DS online without a prescription?
A: No, Generic Bactrim DS is a prescription-only antibiotic and must be used under the supervision of a healthcare provider. EZ Chemist provides this medication upon uploading a valid prescription.

Q2: How long does it take for Bactrim DS to work?
A: Most users notice improvement within 2 to 3 days of starting therapy. However, it is essential to complete the entire prescribed course to prevent recurrence or resistance.

Q3: Can I take Bactrim DS with food?
A: Yes, taking Bactrim DS with food or milk may reduce gastrointestinal side effects.

Q4: What should I do if I miss a dose?
A: Take the missed dose as soon as you remember. If it's close to the time for your next dose, skip the missed one. Do not double dose.

Q5: Can it treat COVID-19 or viral infections?
A: No, Generic Bactrim DS is not effective against viral infections such as the flu or COVID-19.