ANTIBIOTICS / ANTIMICROBIAL DRUGS
A. AMINOGLYCOSIDES
Prototype: Gentamicin (Garamycin)
Action: Acts by suppressing
protein synthesis in bacterial cell; bactericidal.
Use: serious gram-negative
bacterial infections, eye infections.
Adverse effect: toxicity,
nephrotoxicity, neuromuscular blockade, and hypersensitivity photosensitivity
with topical preparations
Related drugs:
- Amikacin (Amikin)
- kanamycin (Kantrex) are
given orally
- Neomycin (Niobiotic) to prepare the bowel for surgery
- Streptomycin
- Tobramycin
- Netilmicin
*Neomycin-
given to persons in hepatic failure to reduce ammonia levels.
B. PENICILLINS
Prototype:
Penicillin G Potassium
Action:
inhibits cells wall synthesis of microorganism; bactericidal
Use:
Systemic infections caused by gram (+) cocci; syphilis, prophylaxis for
rheumatic fever and bacterial endocarditis
Adverse
Effect: Hypersensitivity, G.I upset, potassium poisoning, irritation at
injection site.
Nursing
Implications: give oral form on an empty stomach with a full glass of water; IV
solutions are stable at room temperature for 24 hrs. only
Probenecid:
may be given to increase blood levels of penicillin.
Related drugs:
1.
Penicillinase –resistant penicillins
-used to treat infection caused by
penicillinase producing organism.
Examples: a.) Nafcillin sodium
b.) Cloxacillin
2. Aminopenicillins
-increased
effectiveness against gram negative organism.
Examples: a.) Ampicillin
b.) Amoxicillin
c.) Bacampicillin
3. Extended-spectrum penicillins
-structurally similar to ampicillin
but have an increased spectrum of activity against gram-negative bacteria.
Examples: a.) Carbenicillin
sodium
b.) Piperacillin
4. Penicillin / beta-lactamase
inhibitor combinations
-prevents destruction of penicillin
by enzymes and extend the penicillin’s spectrum of antimicrobial activity.
Examples: Amoxicillin / potassium
clavulanate (Augmentin) Ampicillin/ Sulbactam (Unasyn)
C. CEPHALOSPORINS –divided into 4 generations based on their spectrums of activity.
Prototype for first generation
(ephalozorines- Cefazolin Sodium (Ancef)
Action: Inhibits bacterial cell
wall synthesis; bactericidal.
Use: infection caused by
gram-positive cocci; septicemia; serious intraabdominal infection.
Adverse Effect: Phlebitis at IV
site; diarrhea, pseudomembranous colitis, hypersensitivity, fungal overgrowth,
discomfort at IM injection site, nephrotoxicity, hepatoxicity, bone marrow
depression.
Nursing Implications:
1. Assess for hx of penicillin
allergy as there is a cross allergy between cephalosporin and penicillin.
2. Dose will be reduced with
renal and liver impairment
3. Probenecid therapy will
increase blood levels of cephalosporin.
Related drugs:
a.) Cephalexin (keflex)
b.) Cephradine (Valosef)
Prototype for 2nd
generation Cephalosporins –Cefoxitin Sodium (Mefoxin)
Action: same as above
Use: infection caused by
gram-negative and gram-positive bacteria; septicemia, pelvic skin soft tissue
infections, prophylaxis in abdominal or pelvic surgery; gonorrhea.
Adverse Effect: same as above
Nursing Implications: Lidocaine
is used as diluent for IM injection and helps reduced pain of IM injection.
Related drugs:
a.) Cefaclor (Ceclor)
b.) Cefuroxime sodium
c.) Cefrozil
Prototype for 3rd
generation Cephalosporins –Cefotaxime (Claforan)
Use: Serious infections caused by
gram-negative and gram-positive bacteria
Nursing Implication: Don’t mix
with aminoglycoside solutions; protect IV solution from light.
Related drugs:
a.) Ceftazidime
b.) Ceftriaxone
c.) Cefixine
d.) Cefoperazone
e.) Cefpodoxime
f.) Ceftibuten
Prototype for 4th generation
Cephalosporins –Cefepine (maxipene)
Use: UTI caused by E. coli or
klebsiella pneumonia caused by streptococcus pneumoniae Pseudomonas acryinosa
or enterobacter.
Nursing Implication: have vit. K
available if hypoprothombinemia develops.
Related Drug: Cefditoren
D. MACROLIDES
Prototype: Erythromycin
Action: Inhibits protein
synthesis in bacterial cell, bacteriostatic.
Use: person allergic to
penicillin, legionnaires Disease, mycoplasma pneumonia, intestinal dysenteric
amebiasis, acne, staphylococcal and streptococcal infections.
Adverse Effect: G.I irritation,
superintations, allergic reactions, hepatitis, reversible hearing loss.
Nursing Implications:
-Take on empty stomach with a
full glass of water.
-G.I symptoms are dose related
-do not give with acids
-IV must be diluted sufficiently
and administered slowly to avoid venous irritation and thrombophlebitis.
Related drugs:
1.) Erythromycin estolate (Ilosone)
2.) Azithromycin (Zithromax)
3.) Clarithromycin (Biaxin)
4.) Dirithromycin (Dynabac)
E. TETRACYCLINES
Prototype: Tetracycline
hydrochloride (Acromycin V)
Action: broad-spectrum with
bateriostatic action and, at higher doses, bactericidal action; inhibits
bacterial wall synthesis, reduces free fatty acids from triglycerides thus
reducing acne lesions
Use: Chlamydia, mycoplasma,
rickettsia, acne vulgaris, gonorrhea, spirochetes
Adverse Effect: hypersensitivity,
superinfection chelating to teeth and new bome, N/V, diarrhea, colitis,
headache, dizziness, abdominal cramping, photosensitivity.
Nursing Implications:
a.) Avoid use during pregnancy, in nursing women, and in children under age
8 as drug binds to calcium in teeth and new bone growth, which results in tooth
discoloration of permanent teeth and retarded bone growth
b.) Give deep IM
Discharge Teaching:
a.) Take 1hr. before or 2 hrs. After meals and avoid taking with dairy
products, antacids, vitamins and minerals.
b.) Avoid the sun while taking drug and for a few days after therapy is
terminated
c.) Use meticulous hygiene to reduce super infections.
Related Drugs:
- Doxycycline (Vibramycin) –can be administered
with food.
- Minocycline (Minocin) –can be taken with food.
Dizziness and fatigue may occur.
- Demeclocycline (Declomycin) –administer on an
empty stomach; foods high in calcium and iron interfere with absorption.
F. CHLORAMPHENICOL
Prototype: Chloramphenicol
(Chloramycetin)
Action: a synthetic
broad-spectrum agent primarily bacteriostatic but is bactericidal in higher
dose; inhibits protein synthesis
Use: Haemophilus influenzae
meningitis, rickettsia, salmonella typhi, mycoplasma, bactereoides, typoid
fever.
*Chloramphenicol is used only in
severe infections when other antibiotics can not be used due to its severe
adverse effect of aplastic anemia.
*Gray baby syndrome: abdominal
distention, vomiting, pallor, irregular respiration; circulatory collapse.
Adverse Effect: Aplastic Anemia;
neurotoxicity; gray baby syndrome (seen in premature infants, newborn and
children less than 2yrs old), hypersensitivity, N&V, enterocolitis,
superinfections, bitter taste especially after IV injection.
Nursing Implications: Do not give
by IM injection
Discharge Teaching: 1.) inform
physician immediately of fever, fatigue, sore throat, or bruising.
2.) Take drug on empty stomach
unless upset.
G. SULFONAMIDES
Prototype: Sulfisoxazole
(Gantrisin)
Action: prevents conversion of
para-amino benzoic acid (PABA) to folic acid, which is required for bacterial
growth; bacteriostatic, can be bactericidal in high urinary concentrations
Use: UTI, Otitis media, nocardiosis, vaginitis
Adverse effects:
hypersensitivity, Sterens-Johnson syndrome (acute onset of fever,bullae on skin
and ulcers in mucous membranes of lips, eyes, mouth, nasal passages, and
genetalia, pneumonia, joint pain ad prostratin are also seen fever 7 to 10 days
after starting therapy may indicate
sensitization or hemolytic anemia; renal dysfunction hematologic
reaction, G.I reaction; photosensitivity
Nursing Implications: Give oral
form on empty stomach with full glass of water.
Discharge Teaching:
a.) avoid direct sunlight
b.) increased hypoglycemic reactions for patients taking OHA
c.) Oral contraceptives may be unreliable while client is receiving
sulfonamides.
Related drugs:
1.) Sulfasalazine (Azulfidine)-used in treatment of ulceratives colitis,
constains aspirin, so it is contraindicated in clients allergic to salicylates.
2.) Sulfamethoxazole-can be given in combination with trimethoprim.
(bactrim)-used in treatment of UTI, bronchitis, pneumocystis pneumonia.
H. URINARY ANTI-INFECTIVES
1. Methenamine (mandelamine)
-converted to formaldehyde (which is
bactericidal) in the presence of acidic urine
Adverse Effect: N&V, diarrhea
Nursing Implications: -give with
food
-avoid foods, fluids, and
medications that alkalinize urine
2. Nalidixic Acid (Neg Gram)
-bactericidal effect in gram-negative
bacteria by preventing transmission of genetic informations.
Adverse Effect: Photosensitivity,
headache, dizziness
Nursing Implication: give with
food.
3. Nitrofurantoin (Macrodantin)
-interferes with carbohydrates
metabolism of bacteria; bacteriostatic in low concentration, and bactericidal
in high concentrations.
I. VANCOMYCIN
Prototype: Vancomycin
hydrochloride (Vancocin)
Action: interferes with cell
membrane synthesis and exhibits a bactericidal and bacteriostatic effect.
Use: staphylococcus infections,
pseudomembranous colitis, grain positive organism s, penicillin and methicillin
resistant bacteria
Adverse Effect: Ototoxicity,
nephrotoxicity, hypersensitivity, thrombophlebitis, red-neck syndrome:
(flushing and hypotension from rapid infusion), superifection.
J. FLUOROQUINOLONES
Prototype: Ciprofloxacin (Cipro)
Actions: Inhibits DNA-syrase (an
enzymes needed for replication of bacterial DNA) bactericidal
Use: pseudomonas infections,
gram-negative urinary tract infections or gram-negative systemic infections
Adverse Effect: N&V,
diarrhea, headache, tremors
Nursing Implications:
a.) administer with a large glass of water to prevent crystalluria
b.) Do not give with antacids.
c.) Give 2hrs after meals.
Related drugs:
- Norfloxacin
- Gatifloxacin (Tequin)
- Leofloxacin
- Sparfloxacin (Zagam)
K. ANTITUBERCULAR DRUGS
Prototype: Isoniazid (INH)
Action: Bacteriostatic and in
high concentration becomes bactericidal
Use: initial treatment of
tuberculosis; prophylactic treatment of tuberculosis in high risks group.
Adverse Effect: peripheral
neuritis, jaundice, nausea, blood dyscrasis
Nursing Implications: give vit
B6; on empty stomach, tyramine rich foods should be avoided; avoid
histamine-containing foods as they may cause an exaggerated drug response;
avoid alcohol
Related drugs:
1.) Ethambutol
Adverse Effect: optic neuritis, a
loss of red green color discrimination, and decreased visual acuity can occur
with dosages of 250mg
2.) Rifampicin –body fluids may
turn orange.
3.) Streptomycin –damage to
cranial nerve VIII
-renal toxicity
4.) Pyrazinamide –excess uric acid levels, w/c can cause gout
or hepatic.