Penicillin G is an acid that is combined with sodium, potassium, procaine, or benzathine to increase its stability or to regulate its absorption. The latter two are “long-acting” forms. Penicillin G is useful in the treatment of streptococcal infections due to S. pyogenes (group A), S. agalactiae (group B), S. pneumoniae, viridans streptococci, Corynebacterium diphtheria, N. meningitidis, many strains of N. gonorrhea, Treponema pallidum, and many anaerobic streptococci, such as peptococcus and peptostreptococcus.
Aminoglycosides – antibiotic agents
Aminoglycosides are very potent bactericidal antibiotic agents that are active against susceptible aerobic microorganisms. They kill by inhibiting protein synthesis and to some extent by lysing the cell envelope. All the aminoglycosides (streptomycin, kanamycin, neomycin, gentamicin, amikacin, tobramycin, sisomicin, and netilmicin) share common structural features. Streptomycin is used once a day in combination with other antibiotics to treat mycobacterial infections.
Vancomycin Glycopeptides
Vancomycin and teicoplanin are the only members of this class of antibiotics. Vancomycin is a high-molecular-weight glycopeptide that is bactericidal for gram-positive microorganisms. It inhibits cell-wall synthesis. Given parenterally, it is the drug of choice for methicillin-resistant staphylococcal infections.
Macrolides: Erythromycin, Clarithromycin, Azithromycin
Erythromycin is a macrolide antibiotic that binds to the 50-S subunit of the ribosomes. It kills susceptible bacteria by interfering with their protein synthesis.
Antifungal Drugs
A number of systemic fungal infections (e.g., histoplasmosis, coccidioidomycosis, and paracoccidioidomycosis) can also afflict otherwise healthy persons. Until recently, only amphotericin B was available to treat systemic fungal infection. However, with the rapid development and clinical assessment of azole compounds, a number of these agents are also considered appropriate for treatment of fungal infections.
Antiretroviral Agents General Statement
Decisions regarding when to initiate or modify antiretroviral therapy should be guided by monitoring plasma HIV-1 RNA levels (viral load), CD4+ T-cell counts, and the clinical condition of the patient. Although various other surrogate markers and laboratory parameters were used in the past to assess the risk of progression of HIV infection and evaluate efficacy of antiretroviral agents.
Antiretroviral Therapy in Previously Treated Pediatric Patients
Progressive neurodevelopmental deterioration is defined as persistence or progression of deterioration documented on repeated testing as demonstrated by the presence of 2 or more of the following findings: impairment in brain growth, decline in cognitive function documented by psychometric testing, or clinical motor dysfunction. If there is evidence of progressive neurodevelopmental deterioration, the new antiretroviral regimen optimally should include at least one drug that has substantial CNS penetration (e.g., zidovudine or nevirapine).
Patient Compliance and Issues Related to Dosage and Administration
Patient compliance with recommended regimens (even when asymptomatic) is essential to the potential benefits of antiretroviral therapy. Adherence to antiretroviral regimens is an important determinant of both the degree and duration of virologic suppression. Excellent adherence has been shown to increase the likelihood of sustained virologic control, which is important for reducing HIV-associated morbidity and mortality. Poor adherence has been shown to increase the likelihood of virologic failure and can lead to the development of resistance and limit the effectiveness of antiretroviral therapy.
Drug Interactions Among the Antiretroviral Agents
While further study is needed, data are accumulating regarding pharmacokinetic interactions among the various antiretroviral agents, especially those involving the HIV protease inhibitors and NNRTIs, and the need for dosage adjustments as a result of these interactions. While some pharmacokinetic interactions between antiretroviral agents can be used for therapeutic advantage (e.g., use of low-dose ritonavir to boost plasma concentrations of some other HIV protease inhibitors), other interactions can result in suboptimal drug concentrations and reduced therapeutic effects and should be avoided. The pharmacokinetic interaction between ritonavir and other HIV protease inhibitors is now used for therapeutic advantage in various antiretroviral regimens.
HIV Protease Inhibitors
The fact that hyperglycemia, new-onset diabetes mellitus, exacerbation of preexisting diabetes mellitus, and diabetic ketoacidosis have occurred in HIV-infected individuals receiving HIV protease inhibitors should be considered when these drugs are used during pregnancy. Because pregnancy is itself a risk factor for hyperglycemia and it is not known whether use of an HIV protease inhibitor exacerbates this risk, glucose concentrations should be monitored closely in pregnant women receiving these drugs and these women should be advised about the warning signs of hyperglycemia and diabetes (e.g., increased thirst and hunger, unexplained weight loss, increased urination, fatigue, dry or itchy skin).