USUAL DOSE. 1 g every 6 hours as directed by the physician, intramuscularly or intravenously.
ACTION AND USE. Nafcillin is stable in acidic solution, soluble in water, and readily absorbed. Its action and effect are similar to the other penicillinase-resistant penicillins. Like methicillin, nafcillin is reserved for penicillinaseproducing staphylococcal infections and should not be used for organisms susceptible to penicillin G.
USUAL DOSE. 500 mg or 1 g every 4 to 6 hours as directed by the physician. CEPHALOSPORINS The cephalosporins are a group of semisynthetic derivatives of cephalosporin C, an antimicrobial agent of fungal origin. They are structurally and pharmacologically related to the penicillins. Because the cephalosporins are structurally similar to the penicillins, some patients allergic to penicillin may be allergic to a cephalosporin drug. The incidence of cross-sensitivity is estimated to be 5 to 16 percent. Their antibacterial activity is due to inhibition of cell wall synthesis. This family of antibiotics is generally divided into generations: first generation, cephadrine and cefazolin; second generation, cefoxitin, and third generation, cefotaxime. The main differences between groups is the change in the antibacterial spectrum. The third generation agents have a much broader gram-negative spectrum than the earlier generations.
ACTION AND USE. Cefazolin is indicated for susceptible infections due to Streptococcus pneumonia, Klebsiella, Hemophilus influenza, Staphylococcus aureus, E. coli, and preoperative prophylaxis.
USUAL DOSE. It may be given intramuscularly or intravenously from 250 to 500 mg every 8 hours; 1 to 1.5 g every 6 hours in lifethreatening infections.
ACTION AND USE. Cephadrine is indicated for certain respiratory tract infection, otitis media, certain urinary tract infections, infections of the skin and skin structures, and other susceptible infections.
USUAL DOSE. It may be given parenterally or orally. Orally, give 250 mg every 6 hours or 500 mg every 12 hours. Parenterally, give 2 to 4 g in equally divided doses four times daily intramuscularly or intravenously.
ACTION AND USE. Cefoxitin is used in the treatment of susceptible gram-positive and gram-negative bacteria.
USUAL DOSE. 1 or 2 g every 6 to 8 hours.
ACTION AND USE. Cephalexin is an oral preparation indicated for the treatment of certain respiratory tract infections including group A beta-hemolytic streptococci, otitis media, certain urinary tract infections, osteitis, infections of the skin and skin structures, and other susceptible infections.
USUAL DOSE. 250 to 500 mg four times daily.
ACTION AND USE. Cephalothin is a broad-spectrum parenteral preparation indicated for serious infections caused by susceptible microorganisms specifically S. pneumonia, P. mirabilus, Klebsiella, and E. coli. It is also indicated as a prophylactic measure in certain surgical procedures that are considered contaminated or potentially contaminated.
USUAL DOSE. The usual dose is 500 mg to 1 g every 4 to 6 hours; 500 mg every 6 hours is usually adequate in uncomplicated infections.
The tetracycline, introduced in 1948, were the first truly broad-spectrum antibiotics. They include a large group of drugs with a common basic