Sulfamethox/tmp 80-16mg/5ml Inj

Sulfamethoxazole (SMX) inhibits bacterial dihydrofolate synthesis by competing with para-aminobenzoic acid (PABA) for incorporation into dihydrofolic acid. Trimethoprim (TMP) inhibits bacterial dihydrofolate reductase, an enzyme that converts dihydrofolic acid to tetrahydrofolic acid. This sequential blockade of two steps in the bacterial folic acid synthesis pathway results in a synergistic bactericidal effect, leading to inhibition of bacterial growth and replication.

Urgent Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:

Signs of an allergic reaction: rash, hives, itching, red, swollen, blistered, or peeling skin with or without fever, wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Signs of high potassium levels: abnormal heartbeat, confusion, weakness, lightheadedness, dizziness, numbness or tingling, or shortness of breath.
Signs of low blood sugar: dizziness, headache, sleepiness, weakness, shaking, rapid heartbeat, confusion, hunger, or sweating.
Signs of kidney problems: inability to urinate, changes in urine output, blood in the urine, or significant weight gain.
Signs of low sodium levels: headache, difficulty focusing, memory problems, confusion, weakness, seizures, or balance changes.
Signs of lung or breathing problems: shortness of breath, trouble breathing, cough, or fever.
Signs of pancreatitis (pancreas problem): severe stomach pain, severe back pain, or severe nausea and vomiting.
Muscle or joint pain.
Purple patches on the skin or mouth.
Hallucinations (seeing or hearing things that are not there).
Depression or other mood changes.
Abnormal burning, numbness, or tingling sensations.
Ringing in the ears.
Swollen glands.
Chest pain.
Pale skin.
Severe dizziness or fainting.

Antibiotic-Related Side Effects

Diarrhea is a common side effect of antibiotics. In rare cases, a severe form of diarrhea called C. diff-associated diarrhea (CDAD) may occur, which can lead to life-threatening bowel problems. If you experience stomach pain, cramps, or loose, watery, or bloody stools, contact your doctor immediately. Do not treat diarrhea without consulting your doctor.

Rare but Serious Side Effects

Sulfa drugs, like this medication, can cause rare but severe side effects, including liver problems, blood disorders, and severe skin reactions (Stevens-Johnson syndrome/toxic epidermal necrolysis). If you notice any of the following symptoms, seek medical attention right away:
Rash
Red, swollen, blistered, or peeling skin
Red or irritated eyes
Sores in the mouth, throat, nose, or eyes
Fever, chills, or sore throat
New or worsening cough
Extreme fatigue or weakness
Bruising or bleeding
Signs of liver problems: dark urine, fatigue, decreased appetite, nausea, stomach pain, light-colored stools, vomiting, or yellow skin and eyes.

Other Serious Side Effects

This medication may increase the risk of:
Aseptic meningitis (a severe brain problem): Seek medical help if you experience headache, fever, chills, severe nausea and vomiting, stiff neck, rash, sensitivity to light, sleepiness, or confusion.
Hemophagocytic lymphohistiocytosis (HLH) (a life-threatening immune system problem): Contact your doctor if you notice fever, swollen glands, rash, seizures, confusion, balance changes, or new or worsening difficulty walking.

Administration-Related Side Effects

This medication may cause vein irritation. If the medication leaks from the vein, it can cause irritation around the injection site. Inform your nurse if you experience redness, burning, pain, swelling, or fluid leakage at the injection site.

Common Side Effects

Most people do not experience severe side effects, but some may have mild or moderate side effects. If you notice any of the following symptoms, contact your doctor or seek medical attention if they bother you or do not go away:
Diarrhea
Stomach pain
Nausea
Vomiting
* Decreased appetite

Reporting Side Effects

If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following conditions to ensure safe treatment:

Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Describe the allergic reaction you experienced, including any symptoms.
A history of anemia caused by a lack of folic acid.
Presence of kidney disease or liver disease.
Other health conditions, including:
+ Asthma
+ Porphyria
+ Thyroid disease
+ Folate deficiency
+ Malabsorption
+ Poor nutrition
Long-term alcohol consumption or current use of seizure medications.
Previous experience with low platelet counts while taking trimethoprim or sulfa (sulfonamide) drugs.

Additionally, disclose any current or recent use of the following medications:

Amantadine
Cyclosporine
Dofetilide
Indomethacin
Leucovorin
Methotrexate
Pyrimethamine
Angiotensin-converting enzyme (ACE) inhibitors, such as:
+ Benazepril
+ Captopril
+ Enalapril
+ Fosinopril
+ Lisinopril
+ Moexipril
+ Perindopril
+ Quinapril
+ Ramipril
+ Trandolapril
Diuretics (water pills)

Special Considerations for Children:

This medication is not recommended for infants under 2 months of age. Do not administer this medication to children younger than 2 months old.

It is crucial to provide your doctor and pharmacist with a comprehensive list of all your medications, including prescription and over-the-counter drugs, natural products, and vitamins, as well as any health problems you may have. This information will help your healthcare team determine the safety of taking this medication with your other treatments. Never start, stop, or change the dose of any medication without consulting your doctor.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Regular blood work and laboratory tests, as directed by your doctor, are crucial to monitor your condition. Be aware that this drug may interfere with certain lab tests, so it is vital to notify all your healthcare providers and laboratory personnel that you are taking this medication.

Do not exceed the recommended duration of treatment, as this may increase the risk of a second infection. If you have a deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD), you may be more susceptible to anemia. Individuals of African, South Asian, Middle Eastern, and Mediterranean descent are more likely to have low G6PD levels.

If you have diabetes, it is crucial to closely monitor your blood sugar levels. Before consuming alcohol, consult with your doctor to discuss any potential risks. This medication may increase your sensitivity to the sun, making you more prone to sunburn. Take necessary precautions when exposed to sunlight, and inform your doctor if you experience excessive sunburning while taking this medication.

A severe and potentially life-threatening reaction, known as a hypersensitivity reaction, has been reported in some cases. This reaction may manifest with symptoms such as fever, rash, swollen glands, and problems affecting various organs, including the liver, kidney, blood, heart, muscles, joints, and lungs. If you have any concerns or questions, consult with your doctor.

If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects. Women who are pregnant or become pregnant while taking this medication should immediately contact their doctor, as it may harm the unborn baby. If you are breastfeeding, discuss the potential risks to your baby with your doctor.

If you have a sulfite allergy, consult with your doctor, as some products may contain sulfites. This medication contains propylene glycol, which can cause serious health problems, including nervous system, kidney, and other organ problems, if excessive amounts are ingested. If you have any questions or concerns, consult with your doctor.

Some products may contain benzyl alcohol, which can cause serious side effects in newborns and infants. If possible, avoid products containing benzyl alcohol in these age groups, and consult with your doctor to determine if this product contains benzyl alcohol.

• Dofetilide (increased dofetilide levels, risk of arrhythmias)
• Methotrexate (increased methotrexate levels, increased myelosuppression)

• Warfarin (potentiates anticoagulant effect, increased bleeding risk)
• Phenytoin (increased phenytoin levels, risk of toxicity)
• Digoxin (increased digoxin levels, risk of toxicity, especially in elderly)
• Potassium-sparing diuretics (e.g., spironolactone, amiloride), ACE inhibitors, ARBs (increased risk of hyperkalemia)
• Cyclosporine (decreased cyclosporine levels, increased risk of nephrotoxicity)
• Pyrimethamine (increased risk of megaloblastic anemia)
• Lamivudine (increased lamivudine levels)
• Procainamide (increased procainamide levels)
• Rifampin (decreased TMP levels)
• Oral hypoglycemics (sulfonylureas) (increased hypoglycemic effect)

• Thiazide diuretics (increased risk of thrombocytopenia with purpura in elderly)
• Amantadine (increased amantadine levels, risk of toxicity)
• Memantine (increased memantine levels)
• Zidovudine (increased zidovudine levels, increased myelosuppression)
• Tricyclic antidepressants (increased TCA levels)
• Indomethacin (increased SMX levels)
• Methenamine (risk of crystalluria)

• Antacids (may decrease absorption of oral forms, less relevant for IV)
• Vaccines (live bacterial vaccines, e.g., typhoid, may be less effective)

• Skin rash (including severe forms like SJS/TEN)
• Sore throat, fever, pallor, bruising, unusual bleeding (signs of blood dyscrasias)
• Jaundice, dark urine, abdominal pain (signs of hepatotoxicity)
• Signs of kidney stones or crystalluria (e.g., flank pain, hematuria)
• Signs of hyperkalemia (e.g., muscle weakness, fatigue, palpitations)
• Signs of hypersensitivity reactions (e.g., anaphylaxis, angioedema)
• Neurological symptoms (e.g., aseptic meningitis, peripheral neuropathy, seizures)

Category D. Should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Avoid use during the first trimester due to potential teratogenic effects (folate antagonism) and near term due to risk of kernicterus in the neonate.

L3 (Moderate Risk). Both sulfamethoxazole and trimethoprim are excreted into breast milk. Potential risks to the infant include kernicterus (especially in jaundiced, premature, or G6PD-deficient infants) and hypersensitivity reactions. Use with caution, and generally avoid in infants <2 months or those with hyperbilirubinemia or G6PD deficiency.

Contraindicated in infants less than 2 months of age due to the risk of kernicterus. Use with caution in children, especially those with G6PD deficiency (risk of hemolytic anemia). Dosing is weight-based. Close monitoring for adverse effects is crucial.

Increased risk of severe adverse reactions, including severe skin reactions, bone marrow depression, and hyperkalemia, especially in patients with renal impairment or those on concomitant medications that affect potassium levels. Close monitoring of renal function, electrolytes, and CBC is essential. Lower doses or extended dosing intervals may be necessary.

• Always dilute the IV solution prior to administration. It must be infused over 60-90 minutes; do not administer by rapid infusion or bolus injection.
• Ensure adequate hydration to prevent crystalluria, especially during high-dose therapy.
• Monitor potassium levels closely, particularly in elderly patients, those with renal impairment, or those receiving ACE inhibitors, ARBs, or potassium-sparing diuretics, due to the risk of hyperkalemia.
• Be vigilant for signs of severe skin reactions (SJS/TEN) and blood dyscrasias; discontinue immediately if suspected.
• Consider folate supplementation (e.g., leucovorin) in patients receiving high doses or prolonged therapy, or those at risk of folate deficiency (e.g., malnourished, elderly, AIDS patients), to mitigate myelosuppression.
• The 5:1 ratio of SMX to TMP in the formulation refers to the active ingredients, but dosing is typically based on the trimethoprim (TMP) component.
• IV formulation is generally reserved for severe infections or when oral administration is not feasible.

• For severe UTIs: Fluoroquinolones (e.g., ciprofloxacin, levofloxacin), Aminoglycosides (e.g., gentamicin), Cephalosporins (e.g., ceftriaxone), Carbapenems (e.g., ertapenem).
• For PJP treatment: Pentamidine (IV), Clindamycin + Primaquine, Atovaquone (oral, for mild cases).
• For Nocardiosis: Imipenem, Amikacin, Linezolid, Minocycline (often in combination).
• For Shigellosis: Azithromycin, Ciprofloxacin (if susceptible).

If your symptoms or health problems persist or worsen, it is essential to contact your doctor for further evaluation and guidance.

To ensure safe and effective use of your medication, please follow these guidelines:

- Do not share your medication with others, and never take someone else's medication.
- Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion.
- Dispose of unused or expired medications properly. Unless instructed otherwise, do not flush medications down the toilet or pour them down the drain. Instead, consult your pharmacist for advice on the best disposal method or inquire about potential drug take-back programs in your area.

For additional information about your medication, you may receive a separate patient information leaflet. If you have any questions or concerns, it is crucial to discuss them with your doctor, nurse, pharmacist, or other healthcare provider.

In the event of a suspected overdose, immediately contact your local poison control center or seek emergency medical attention. Be prepared to provide detailed information about the overdose, including the medication taken, the quantity, and the time it occurred.