Medication Summary
Antibiotic, antiprotozoal, antiviral, or antifungal agents are used, depending on the cause of infection.
Antibiotics
Class Summary
Therapy must be comprehensive and should cover all likely pathogens in the context of this clinical setting.
Penicillin G benzathine (Bicillin L-A, Permapen)
Interferes with synthesis of cell wall mucopeptides during active multiplication, which results in bactericidal activity.
Interferons
Class Summary
Naturally produced proteins with antiviral, antitumor, and immunomodulatory actions. Used for treating hepatitis B and hepatitis C.
Interferon alfa-2b (Intron A)
Indicated for hepatitis B. Protein product manufactured by recombinant DNA technology. Mechanism of antitumor activity not clearly understood; however, direct antiproliferative effects against malignant cells and modulation of host immune response may play important roles.
Anthelmintics
Class Summary
Parasite biochemical pathways are sufficiently different from the human host to allow selective interference by chemotherapeutic agents in relatively small doses.
Praziquantel (Biltricide)
Increases cell membrane permeability in susceptible worms, resulting in loss of intracellular calcium, massive contractions, and paralysis of musculature. In addition, produces vacuolization and disintegration of schistosome tegument. This is followed by attachment of phagocytes to parasite and death. Tabs should be swallowed whole with some liquid during meals. Keeping tabs in mouth may reveal bitter taste, which can produce nausea or vomiting.
Diethylcarbamazine citrate (Hetrazan)
For parasitic infections. Synthetic organic compound highly specific for several common parasites. Does not contain toxic metallic elements. Not recommended as DOC because of more severe adverse effects. Recommended if therapy with mebendazole fails or is not available.
Sodium antimony gluconate (Pentostam)
DOC for the treatment of leishmaniasis in United States. May be administered IV or IM. Intravenous use is preferred because large volumes are required. Available at 100 mg/mL. Dilute each mL in 10 mL of 5% dextrose water and administer over 15 min to prevent thrombophlebitis.
Chloroquine phosphate (Aralen phosphate)
Inhibits growth by concentrating within acid vesicles of parasite, which increases internal pH of organism. Also inhibits hemoglobin utilization and metabolism of parasite.
Antiviral agents
Class Summary
These agents are nucleoside analogs that inhibit viral replication.
Entecavir (Baraclude)
Guanosine nucleoside analogue with activity against HBV polymerase. Competes with natural substrate deoxyguanosine triphosphate to inhibit HBV polymerase activity (ie, reverse transcriptase). Less effective for lamivudine-refractory HBV infection. Indicated for treatment of chronic hepatitis B infection. Available as tab and oral solution (0.05 mg/mL; 0.5 mg = 10 mL).
Lamivudine (Epivir-HBV)
Nucleoside analogue approved by the FDA for chronic hepatitis B treatment. Now considered first-line therapy, eclipsing interferon. Inhibits hepatitis B viral DNA polymerase. Use should be considered in patients with ongoing hepatitis B viral replication, elevated aminotransferase activity, and histologic evidence of liver injury. Consider for cases that failed, are unlikely to respond to interferon, or patients who cannot tolerate interferon. Discontinue lamivudine only when repeated assays demonstrated HBeAg loss or seroconversion to HBeAb. Emergence of resistance is the major drawback of nucleoside analogue monotherapy. Proper management of viral breakthrough in patients treated with lamivudine is not yet defined. Continuation of lamivudine appears to be warranted in most cases because resistant strains of HBV seem to be attenuated and are associated with only mild liver injury.
Note that the available dosage forms differ between Epivir and Epivir-HBV (formula specific for hepatitis B virus). Epivir-HVB is available as a 100 mg tab or oral solution 5 mg/mL, whereas Epivir contains 150 mg/tab or 10 mg/mL in oral solution.
Tables
| Bacterial | Viral | Protozoal |
|---|---|---|
| Staphyloccoccus aureus, S epidermidis, S albus | Hepatitis (A, B, C, E) | Plasmodium malariae, P falciparum, P vivax |
| Streptococcus pneumoniae, S viridans, S pyogenes | Human immunodeficiency virus | Leishmania donovani |
| Mycobacterium leprae, M tuberculosis | Epstein-Barr virus | Toxoplasma gondii |
| Treponema pallidum | Hantavirus | Trypanosoma cruzi, T bruci |
| Salmonella typhi, S paratyphi, S typhimurium | Coxsackie B | Toxocara canis |
| Leptospira species | Echovirus | Strongyloides stercoralis |
| Yersinia enterocolitica | Cytomegalovirus | |
| Neisseria meningitidis, Neisseria gonorrhoeae | Varicella zoster | Helminthic |
| Corynebacterium diphtheriae | Mumps | Schistosoma mansoni, S japonicum, S haematobium |
| Coxiella burnetti | Rubella | Wuchereria bancrofti |
| Brucella abortus | Influenza | Brugia malayi |
| Listeria monocytogenes | Dengue | Loa loa |
| Parvovirus | Onchocerca volvulus | |
| Syphilis | Trichinella spiralis | |
| SARS-CoV-2 (COVID-19) | ||
| Fungal | ||
| Histoplasma capsulatum | ||
| Candida | ||
| Coccidiodes immitis |
