ANTIVIRAL AGENTS
ACYCLOVIR (ZOVIRAX) *Inhibits viral DNA replication. Does not cure nor prevent transmission of herpes infections but decreases the severity & duration of the infection *Indicated for herpes simplex 1 & 2, varicella and herpes zooster infection *A/R crystalluria & phlebitis at injection site ZIDOVUDINE (AZT, RETROVIR) *Developed to control AIDS or ARC (AIDS- Related Complex) *A/R: Leukocytopenia & Anemia, hepatotoxic & nephrotoxic, dizziness..crosses blood & brain barrier *Safe for pregnant women Related Drugs: didanosine (Videx), Lamivudine (Epivir) & Zalcitabine (ddC) ***Nucleoside reverse transcriptase inhibitors indicated for CD4 of 500 & less PROTEASE INHIBITORS saquinavir (Invirase) *A/R: photosensitivity ritonavir (Norvir) *A/R: increase triglyceride levels stavudine (d4T, Zerit) *for those who do not respond to conventional therapy *A/R: peripheral neuropathy, unsteady gait
ANTIBACTERIALS
SULFONAMIDES- SULFISOXAZOLE (GANTRISIN) *Prevents conversion of (PABA) to folic acid which is needed for bacterial growth; bacteriostatic & bactericidal *Used for UTIs, eye infections, otitis media, vaginitis *A/R: Steven-Johnson syndrome (acute onset of fever, bullae on skin & ulcers on mucus membranes of lips, eyes, mouth, nasal passages & genitalia. Pneumonia & joint pains may occur; fever after 7-10 days after onset of therapy indicates hypersensitivity or hemolytic anemia *Caution diabetics that drug may cause hypoglycemia; women on oral contraceptives need an alternative method of contraception PENICILLINS PENICILLIN G POTASSIUM (PENTIDS) *Inhibits cell wall synthesis of microorganisms; bactericidal *Systemic infections of gram-positive cocci; syphilis, prophylaxis for rheumatic fever & bacterial endocarditis *A/R: hypersensitivity; GI upset, nephritis, anemia, leukopenia & thrombocytopenia PENICILLIN G POTASSIUM (PENTIDS) Probenecid (Benemid) may be given to increase blood levels of penicillins
RELATED DRUGS: A. PENICILLINASE-RESISTANT PENICILLINS METHICIN Na (STAPHCILLIN) & NAFCILLIN Na (NAFCIN, UNIPEN) *Used to treat penicillinase-producing organisms B. AMINOPENICILLINS AMPICILLIN (AMCILL, POLYCILLIN) & AMOXICILLIN TRIHYDRATE (AMOXIL) *Increased effectiveness against gram-negative organisms CEPHALOSPORINS FIRST-GENERATION – CEFAZOLIN Na (ANCEF) *Inhibits bacterial cell wall synthesis; bactericidal (same action for all generations) *Against gram-positive cocci *A/R: hypersensitivity; nephrotoxicity & hepato-toxicity; bone marrow depression *Cross-allergy with penicillin *Probenecid therapy SECOND GENERATION – CEFOXITIN Na (MEFOXIN) *Used against gram-negative & gram-positive bacteria *A/R is the same for all generations *Lidocaine used as diluent for IM injection to reduce the pain THIRD GENERATION – CEFOTAXIME (CLAFORAN) *Used in serious gram-negative & gram-positive infections such as neonatal meningitis & gonorrhea *A/R is the same for all generations *Protect IV solutions from light & do not mix with amino-glycosides---nephrotoxic CHLORAMPHENICOL CHLORAMPENICOL (CHLOROMYCETIN) *Inhibits CHON synthesis; bacteriostatic & bactericidal *Used against Haemophilus influenzae meningitis, salmonella typhi- used only in severe infections where other antibiotics can’t be used because A/R are aplastic anemia & gray baby syndrome (seen in premature infant & children below 2 years…experiences vomiting, abdominal distention, irregular respirations & circulatory collapse) QUINOLONES *referred to as quinolone or fluroqinolone CIPROFLOXACIN (CIPROBAY) S/E =N/V, diarrhea, discomfort, dizziness, lightheadedness S/E TO REPORT = rash = neurologic effects: H/A, mental depression DRUG INTERACTION = antacids = probenecid = theophylline TETRACYCLINES TETRACYCLINE HCl (ACHROMYCIN V) *Inhibits bacterial cell wall synthesis; bacteriostatic & bactericidal; reduces fatty acids from triglycerides *Used for acne vulgaris, gonorrhea & spirochetes *A/R: photosensitivity, hepatotoxicity; chelating to teeth and new bones...avoid giving to pregnant & nursing
women, children under 8 as drug binds to Ca in teeth & new bones causing permanently discolored teeth & retarded bone growth
AMINOGLYCOSIDES General Information on all agents GENTAMICIN (GARAMYCIN) “Mycins” *Suppresses protein synthesis in bacterial cell; bactericidal *Against gram-negative bacterial infections; eye infections *A/R: ototoxicity; nephrotoxicity & neuromuscular blockage VANCOMYCIN VANCOMYCIN HCl (VANCOCIN) *Interferes with cell membrane activities; bacteriostatic & bactericidal *Effective against gram (+) cocci like staphylococcus *A/R: ototoxicity, nephrotoxicity, thrombophlebitis, Red-neck syndrome (flushing & hypotension from rapid IV infusion) LINCOMYCINS *Clindamycin hcl capsules (cleocin, dalacin C) *lincomycin hcl (lincocin) - semisynthetic derivative of lincomycin, is more effective & causes fewer untoward effects MACROLIDES ERYTHROMYCINS – ERYTHROMYCIN BASE (E-MYCIN) *Inhibits protein synthesis in bacterial cell; bacteriostatic *Used in persons with allergy to penicillins; indicated for acne, streptococcal & staphylococcal infections *A/R: GI irritation, allergic reactions, hepatitis, reversible hearing loss *Do not give with acids e.g. orange juice
ANTIFUNGALS
Amphoterizin B (fungizone) * shld be mixed only w/ water & slowly infuse * BUN, liver enzymes, u/a shld be checked Butoconazole nitrate (femstat) Ketonazole (nizoral) Miconazole (monistat) Nystatin (mycostatin)
ANTITUBERCULARS
General Considerations ISONIAZID (INH) *Initial TTT against PTB; prophylaxis for high-risk groups *A/R: peripheral neuritis…give vitamin B6 (pyridoxine); hepatitis…check liver enzymes frequently;
hyperexcitability *Taken on empty stomach, avoid alcohol & interferes with Phenytoin (Dilantin) requiring lowering of INH dose ETHAMBUTOL (MYAMBUTOL) *A/R: optic neuritis & loss of red-green color discrimination but it’s reversible RIFAMPICIN *A/R: hepatitis, flu-like syndrome, may turn body fluids (urine, tears, saliva etc.) orange *Interacts with anticoagulants, oral contraceptives, oral hypoglycemics, methadone & corticosteroids STREPTOMYCIN *A/R: cranial nerve 8 damage (roaring, ringing & feeling of fullness in the ear); vestibular damage (dizziness & vertigo) PYRAZINAMIDE *A/R: increased uric acid causing gout or hepatitis