What is Trimethoprim
Trimethoprim is a synthetic antiinfective agent. It has activity against both gram-positive and gram-negative bacteria.
It is commonly used systemically for the treatment and prophylaxis of uncomplicated urinary tract infections, for traveler’s diarrhea, and, when combined with either sulfamethoxazole or dapsone, for prophylaxis and treatment of Pneumocystis infections.
Trimethoprim was originally available in combination with sulfamethoxazole in 1973, then was approved by the FDA for use as a single agent in 1980. It is also available in an ophthalmic solution in combination with polymyxin B.
Indications
- Acinetobacter sp.
- Citrobacter sp.
- cystitis
- Enterobacter sp.
- Escherichia coli
- Haemophilus influenzae (beta-lactamase negative)
- Haemophilus influenzae (beta-lactamase positive)
- Klebsiella pneumoniae
- otitis media
- Pneumocystis jirovecii (formerly Pneumocystis carinii)
- Pneumocystis pneumonia (PCP)
- Proteus mirabilis
- Salmonella sp.
- Shigella sp.
- Staphylococcus epidermidis
- Staphylococcus saprophyticus
- Streptococcus pneumoniae
- Streptococcus pyogenes (group A beta-hemolytic streptococci)
- urinary tract infection (UTI)
- urinary tract infection (UTI) prophylaxis
Side Effects
- abdominal pain
- acute generalized exanthematous pustulosis (AGEP)
- aseptic meningitis
- azotemia
- candidiasis
- cholestasis
- diarrhea
- elevated hepatic enzymes
- exfoliative dermatitis
- fever
- glossitis
- hyperbilirubinemia
- hyperkalemia
- hyponatremia
- jaundice
- leukopenia
- maculopapular rash
- megaloblastic anemia
- methemoglobinemia
- nausea
- neutropenia
- photosensitivity
- pruritus
- pseudomembranous colitis
- rash
- Stevens-Johnson syndrome
- superinfection
- thrombocytopenia
- toxic epidermal necrolysis
- vomiting
Monitoring Parameters
- CBC
- serum creatinine/BUN
Contraindications
- breast-feeding
- colitis
- diarrhea
- folate deficiency
- folate deficiency megaloblastic anemia
- geriatric
- GI disease
- hepatic disease
- hyperkalemia
- infants
- inflammatory bowel disease
- neonates
- pregnancy
- pseudomembranous colitis
- renal disease
- renal failure
- renal impairment
- ulcerative colitis
Interactions
- Abacavir; Lamivudine, 3TC; Zidovudine, ZDV
- Aliskiren; Valsartan
- Alogliptin; Pioglitazone
- Amantadine
- Amiloride
- Amiloride; Hydrochlorothiazide, HCTZ
- Amlodipine; Benazepril
- Amlodipine; Hydrochlorothiazide, HCTZ; Olmesartan
- Amlodipine; Hydrochlorothiazide, HCTZ; Valsartan
- Amlodipine; Olmesartan
- Amlodipine; Telmisartan
- Amlodipine; Valsartan
- Angiotensin II receptor antagonists
- Angiotensin-converting enzyme inhibitors
- Atovaquone
- Atovaquone; Proguanil
- Azathioprine
- Azilsartan
- Azilsartan; Chlorthalidone
- Benazepril
- Benazepril; Hydrochlorothiazide, HCTZ
- Candesartan
- Candesartan; Hydrochlorothiazide, HCTZ
- Captopril
- Captopril; Hydrochlorothiazide, HCTZ
- Citric Acid; Potassium Citrate
- Citric Acid; Potassium Citrate; Sodium Citrate
- Dapsone
- Dasabuvir; Ombitasvir; Paritaprevir; Ritonavir
- Dextromethorphan; Guaifenesin; Potassium Guaiacolsulfonate
- Dienogest; Estradiol valerate
- Digoxin
- Dofetilide
- Donepezil; Memantine
- Drospirenone
- Drospirenone; Estradiol
- Drospirenone; Ethinyl Estradiol
- Drospirenone; Ethinyl Estradiol; Levomefolate
- Elagolix; Estradiol; Norethindrone acetate
- Eltrombopag
- Enalapril, Enalaprilat
- Enalapril; Felodipine
- Enalapril; Hydrochlorothiazide, HCTZ
- Entecavir
- Eplerenone
- Eprosartan
- Eprosartan; Hydrochlorothiazide, HCTZ
- Estradiol; Levonorgestrel
- Estradiol; Norethindrone
- Estradiol; Norgestimate
- Ethinyl Estradiol
- Ethinyl Estradiol; Desogestrel
- Ethinyl Estradiol; Ethynodiol Diacetate
- Ethinyl Estradiol; Etonogestrel
- Ethinyl Estradiol; Levonorgestrel
- Ethinyl Estradiol; Levonorgestrel; Ferrous bisglycinate
- Ethinyl Estradiol; Levonorgestrel; Folic Acid; Levomefolate
- Ethinyl Estradiol; Norelgestromin
- Ethinyl Estradiol; Norethindrone
- Ethinyl Estradiol; Norethindrone Acetate
- Ethinyl Estradiol; Norethindrone Acetate; Ferrous fumarate
- Ethinyl Estradiol; Norethindrone; Ferrous fumarate
- Ethinyl Estradiol; Norgestimate
- Ethinyl Estradiol; Norgestrel
- Fluorouracil, 5-FU
- Folic Acid, Vitamin B9
- Fosinopril
- Fosinopril; Hydrochlorothiazide, HCTZ
- Fosphenytoin
- Ganciclovir
- Glimepiride; Pioglitazone
- Glimepiride; Rosiglitazone
- Guaifenesin; Potassium Guaiacolsulfonate
- Hetastarch; Dextrose; Electrolytes
- Hydrochlorothiazide, HCTZ; Irbesartan
- Hydrochlorothiazide, HCTZ; Lisinopril
- Hydrochlorothiazide, HCTZ; Losartan
- Hydrochlorothiazide, HCTZ; Moexipril
- Hydrochlorothiazide, HCTZ; Olmesartan
- Hydrochlorothiazide, HCTZ; Quinapril
- Hydrochlorothiazide, HCTZ; Spironolactone
- Hydrochlorothiazide, HCTZ; Telmisartan
- Hydrochlorothiazide, HCTZ; Triamterene
- Hydrochlorothiazide, HCTZ; Valsartan
- Hydrocodone; Potassium Guaiacolsulfonate
- Hydrocodone; Potassium Guaiacolsulfonate; Pseudoephedrine
- Ibritumomab Tiuxetan
- Indinavir
- Iodine; Potassium Iodide, KI
- Irbesartan
- Isoniazid, INH; Pyrazinamide, PZA; Rifampin
- Isoniazid, INH; Rifampin
- Lamivudine, 3TC; Zidovudine, ZDV
- Lamotrigine
- Leucovorin
- Leuprolide; Norethindrone
- Levoleucovorin
- Levomefolate
- Levonorgestrel
- Lisinopril
- Loperamide
- Loperamide; Simethicone
- Losartan
- Mefenamic Acid
- Memantine
- Mestranol; Norethindrone
- Metformin; Pioglitazone
- Metformin; Repaglinide
- Metformin; Rosiglitazone
- Methotrexate
- Moexipril
- Nanoparticle Albumin-Bound Paclitaxel
- Nebivolol; Valsartan
- Norethindrone
- Norgestrel
- Olmesartan
- Omeprazole; Amoxicillin; Rifabutin
- Oral Contraceptives
- Paclitaxel
- Perindopril
- Perindopril; Amlodipine
- Phenytoin
- Pioglitazone
- Potassium
- Potassium Acetate
- Potassium Bicarbonate
- Potassium Chloride
- Potassium Citrate
- Potassium Gluconate
- Potassium Iodide, KI
- Potassium Phosphate
- Potassium Phosphate; Sodium Phosphate
- Potassium-sparing diuretics
- Pralatrexate
- Procainamide
- Pyrimethamine
- Pyrimethamine; Sulfadoxine
- Quinapril
- Ramipril
- Repaglinide
- Rifabutin
- Rifampin
- Rosiglitazone
- Sacubitril; Valsartan
- Sapropterin
- Segesterone Acetate; Ethinyl Estradiol
- Selexipag
- Sodium picosulfate; Magnesium oxide; Anhydrous citric acid
- Sofosbuvir; Velpatasvir
- Sofosbuvir; Velpatasvir; Voxilaprevir
- Spironolactone
- Telmisartan
- Terbinafine
- Tolbutamide
- Trandolapril
- Trandolapril; Verapamil
- Triamterene
- Trimetrexate
- Trospium
- Valganciclovir
- Valproic Acid, Divalproex Sodium
- Valsartan
- Zidovudine, ZDV