Aminoglycosides
Aminoglycosides – ‘The 3 Amigos’
⭐ AMINOglycosides are antibiotics comprised of AMINO acid sugars that are linked together.
3️⃣ The three most commonly used are (mnemonic: TAG):
-Tobramycin
-Amikacin
-Gentamicin
Other agents include plazomicin, streptomycin, and neomycin.
⭐ They are used for serious infections caused by gram-negative bacteria such as complicated UTIs, sepsis, or intraabdominal infections. They can also be used in combination with other agents for infectious caused by gram-positive bacteria in endocarditis.
⭐ MOA: they kill bacteria by binding onto 30S ribosomal subunits inhibiting the bacteria’s ability to synthesize proteins, leading to cell death
⭐ Other key facts to know:
-Adverse effects include nephrotoxicity and ototoxicity
-They are approximately 70-95% excreted renally
-They are concentration-dependent bacterial killers, which means bacterial killing increases with rising drug concentrations
-Monitor serum drug levels (troughs and peaks), serum creatinine, BUN, urine output, and hearing.
Test your knowledge and check your answers on the second slide.
Lithium is a common ‘mood stabilizer’ used to treat the manic episodes of bipolar disorder, a mood disorder that is characterized by episodes of mania, hypomania, and depression. ⠀
The exact cause of bipolar disorder is unknown but is highly linked to family history, genetics, and abnormalities in neurotransmitters. This makes it tricky to pinpoint exactly how lithium works to treat bipolar but there are many proposed mechanisms of action. ⠀
Whenever you see the medication lithium, always think SALT as lithium (Li+) is located close to sodium (Na+) on the periodic table and they share similar structures. Because of this, lithium levels are often affected by salt and water balance as well as renal function (excreted mainly through kidneys). ⠀
Dehydration can cause lithium levels to increase while increasing sodium intake can cause lithium levels to decrease. Medications that affect water and salt balance (ex: diuretics, NSAIDs, ACEI) can also alter lithium concentrations. ⠀
The starting dose of lithium is 300 mg two or three times a day (The brand name is Lithobid to help you remember that it can be given BID or twice daily)⠀
Lithium is considered teratogenic due to the potential for fetal cardiac defects. The risks and benefits should be discussed with a healthcare provider before starting it in women of childbearing age.⠀
Major depressive disorder (MDD) is a mood disorder characterized by persistent feelings of sadness and loss of interest that interferes with normal daily functioning.
Because of this, the drugs developed to treat MDD selectively target the reuptake of serotonin and norepinephrine, increasing levels of these neurotransmitters in the synapse and enhancing NT signaling.
MOA: binds to D-alanyl-D-alanine on the outer surface of cell membranes preventing cross-linking. This interferes with cell wall synthesis and results in bacterial cell death. 