Trimethoprim, Toxoplasma Gondii, Shigella mnemonic - Pharmacology mnemonics and tutorial

Trimethoprim [Tri methyl prime]

Blocks the bacterial synthesis of folate [foliage] from dihydrofolate [two drops dripping from foliage] by inhibition of dihydrofolate reductase
Weak base, and so is ionized and trapped in acidic tissues, such as prostate [lithmus paper pH meter shifts to red (acidic) side]
Effective against:
- Gram (-) urinary tract and prostate infections [red bacilli in bladder & prostate]
- Toxoplasma gondii [Ghandi holding a cat, bleeding bullet hole from the prime]
- Shigella [shagging Ella - red immotile (rooted) bacillus causing dysentery]
Adverse effects include megaloblastic anemia [ballooning erythrocyte]
- This effect can be alleviated by coadministration of folinic acid [balloon string cut by foliage-nick]
Also can cause leukopenia and granulocytopenia