Penicillin (redirected from B-Cillin K)

penicillin /pen·i·cil·lin/ (pen?i-sil´in) any of a large group of natural (p. G, p.V) or semisynthetic antibacterial antibiotics derived directly or indirectly from strains of fungi of the genus Penicillium and other soil-inhabiting fungi, which exert a bactericidal as well as a bacteriostatic effect on susceptible bacteria by interfering with the final stages of the synthesis of peptidoglycan, a substance in the bacterial cell wall. The penicillins, despite their relatively low toxicity for the host, are active against many bacteria, especially gram-positive pathogens (streptococci, staphylococci, pneumococci); clostridia; some gram-negative forms (gonococci, meningococci); some spirochetes (Treponema pallidum and T. pertenue ); and some fungi. Certain strains of some target species, e.g., staphylococci, secrete the enzyme penicillinase, which inactivates penicillin and confers resistance to the antibiotic.

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pen·i·cil·lin (pn-sln)

n.

Any of a group of broad-spectrum antibiotic drugs obtained from penicillium molds or produced synthetically, most active against gram-positive bacteria and used in the treatment of various infections and diseases.

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penicillin (pen´isil´in),

n an antibiotic secured from cultures of
P. notatum, being bactericidal for gram-positive cocci, some gram-negative cocci (gonococcus and meningococcus), and clostridial and spirochetal organisms. Its topical application to the oral mucusa membranes is discouraged because of the high risk of sensitization from local application of antibiotic substances.

penicillin G,

n an acid-sensitive form of penicillin prepared as penicillin G benzathine and penicillin G procaine used for deep intramuscular administration. It is slowly released, resulting in prolonged effective blood levels. In past dentistry, it was used prophylactically for patients predisposed to bacterial endocarditis prior to any invasive dental procedure. Now it has been replaced by amoxicillin. It has a high allergy potential. See also penicillin G benzathine.

penicillin G benzathine,

n brand names: Bicillin L-A, Permapen;
drug class: benzathine salt of natural penicillin;
action: interferes with cell wall replication of susceptible organisms; osmotically unstable cell wall swells and bursts from osmotic pressure;
uses: respiratory infections, scarlet fever, erysipelas, otitis media, pneumonia, skin and soft tissue infections, and yaws.

penicillin V potassium/penicillin V,

n brand names: Beepen-VK, Betapen-VK, V-Cillin K, Veetids, others;
drug class: semisynthetic penicillin;
action: interferes with cell wall replication of susceptible organisms; the cell wall, rendered osmotically unstable, swells and bursts from osmotic pressure;
uses: effective for both gram-positive cocci and gram-negative bacilli.

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penicillin

any of a large group of natural or semisynthetic antibacterial antibiotics derived directly or indirectly from strains of fungi of the genus Penicillium and other soil-inhabiting fungi grown on special culture media. Penicillins exert a bactericidal as well as a bacteriostatic effect on susceptible bacteria by interfering with the final stages of the synthesis of peptidoglycan, a substance in the bacterial cell wall. Despite their relatively low toxicity for the host, they are active against many bacteria, especially gram-positive pathogens (streptococci, staphylococci); clostridia; certain gram-negative forms; certain spirochetes (Treponema pallidum and T. pertenue); and certain fungi. Certain strains of some target species, for example staphylococci, secrete the enzyme penicillinase, which inactivates penicillin and confers resistance to the antibiotic. Some of the newer penicillins, for example methicillin, are more effective against penicillinase-producing organisms. An additional class of extended-spectrum penicillins has been approved for use; it includes piperacillin and mezlocillin.

There are four groups of penicillins, the natural penicillins, penicillin G and penicillin V, with a narrow spectrum of activity, mainly against gram-positive bacteria; the aminopenicillins (amoxicillin, ampicillin and hetacillin) are semisynthetic derivatives and have a broad spectrum of activity against gram-positive and many gram-negative organisms, but are susceptible to penicillinase-producing Staphylococcus spp.; penicillinase-resistant penicillins, which include cloxacillin, methicillin, nafcillin and oxacillin; and the extended-spectrum penicillins (azlocillin, carbenicillin, mezlocillin, piperacillin and ticarcillin), which are effective against gram-positive and gram-negative organisms, including Pseudomonas aeruginosa.

Allergic reaction to penicillin occurs in some animals. The reaction may be slight—a stinging or burning sensation at the site of injection—or it can be more serious—severe dermatitis or even anaphylactic shock, which may be fatal.

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penicillin allergy

degradation products of the penicillins act as haptens, binding to proteins and stimulating an immune response.

penicillin G

benzylpenicillin; the most widely used penicillin; used principally in the treatment of infections due to gram-positive bacteria. Procaine penicillin G is a parenteral preparation that gives extended action for up to 24 hours and benzathine penicillin G is a very slow-release, parenteral preparation that maintains blood levels for several days.

penicillin-induced hemolytic anemia

rare problem in horses which develop IgG anti-penicillin antibodies.

phenoxymethyl penicillin

a biosynthetically or semisynthetically produced antibiotic, similar to penicillin G, for oral administration; not affected by gastric acid and is suitable for oral administration. Its antibacterial spectrum is the same as for penicillin G. Called also penicillin V.

penicillin V

see phenoxymethyl penicillin (above).

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piperacillin sodium

Pharmacologic class: Penicillin (extended-spectrum)

Therapeutic class: Anti-infective

Pregnancy risk category B

Action

Inhibits bacterial cell-wall synthesis during active multiplication stage, resulting in cell death

Availability

Injection: 2 g, 3 g, 4 g, 40 g

⊘Indications and dosages

➣ To prevent infection during abdominal and vaginal surgery

Adults: For intra-abdominal surgery, 2 g I.V. just before surgery, followed by 2 g during surgery, then 2 g q 6 hours postoperatively for no more than 24 hours. For vaginal hysterectomy, 2 g I.V. just before surgery, followed by 2 g at 6 hours and 2 g at 12 hours after the initial dose. In cesarean delivery, 2 g I.V. after umbilical cord is clamped, followed by 2 g at 4 hours and 2 g at 8 hours after the initial dose. In abdominal hysterectomy, 2 g I.V. just before surgery, followed by 2 g on return to recovery room and 2 g 6 hours later.

➣ Serious infections

Adults: 12 to 18 g/day I.V. in divided doses q 4 to 6 hours

➣ Complicated urinary tract infection (UTI)

Adults: 8 to 16 g/day I.V. in divided doses q 6 to 8 hours

➣ Uncomplicated UTI or community-acquired pneumonia

Adults: 6 to 8 g/day I.M. or I.V. in divided doses q 6 to 12 hours

➣ Uncomplicated gonorrhea

Adults: 2 g I.M. as a single dose, with 1 g probenecid P.O. given 30 minutes before piperacillin injection

Dosage adjustment

• Renal impairment
• Elderly patients
• Children

Contraindications

• Hypersensitivity to penicillin or cephalosporins

Precautions

Use cautiously in:
• uremia, hypokalemia, cystic fibrosis, bleeding tendencies, drug allergies, sodium restriction
• pregnant or breastfeeding patients
• children younger than age 12.

Administration

• Ask patient about allergy to penicillin and cephalosporins before administering.
☞ Keep epinephrine and emergency equipment available.
• For I.M. use, dilute in sterile water for injection or normal saline solution, to yield a final concentration of 400 mg/ml. Limit dosage to 2 g. Preferably, inject into upper outer buttock area.
• For intermittent I.V. infusion, dilute reconstituted solution in 50 ml of dextrose 5% in water, normal saline solution, dextrose 5% in normal saline solution, or lactated Ringer's solution. Infuse over 20 to 30 minutes.
• When giving I.V. bolus, inject reconstituted solution over 3 to 5 minutes.
• Don't mix with aminoglycosides in syringe or infusion container; doing so inactivates aminoglycoside.

Route	Onset	Peak	Duration
I.V.	Immediate	Immediate	Dose dependent
I.M.	Unknown	30-50 min	Dose dependent

Adverse reactions

CNS: headache, dizziness, fatigue, seizures

CV: thrombophlebitis, deep-vein thrombosis

GI: nausea, vomiting, constipation, diarrhea, bloody diarrhea, pseudomembranous colitis

Hematologic: hematoma, eosinophilia, neutropenia, leukopenia, thrombocytopenia

Hepatic: cholestatic hepatitis

Metabolic: hypokalemia, hypernatremia, sodium overload

Skin: rash, erythema, induration, bruising, erythema multiforme, Stevens-Johnson syndrome

Other: pain, superinfection, anaphylaxis

Interactions

Drug-drug. Aminoglycosides: aminoglycoside inactivation

Aspirin, probenecid: increased piperacillin blood level

Hormonal contraceptives: decreased contraceptive efficacy

Methotrexate: increased risk of methotrexate toxicity

Tetracyclines: decreased piperacillin efficacy

Vecuronium: prolonged neuromuscular blockade

Drug-diagnostic tests. Bilirubin, blood urea nitrogen, creatinine, eosinophils, hepatic enzymes: increased values

Coombs' test (with I.V. piperacillin): false-positive result

Granulocytes, hemoglobin, platelets, white blood cells: decreased levels

Patient monitoring

☞ Monitor for signs and symptoms of anaphylaxis or superinfection.
☞ Be aware that high doses may cause seizures.
☞ Watch for signs and symptoms of thrombophlebitis and deep-vein thrombosis.
• Assess drug efficacy. Obtain repeat cultures after therapy ends.
☞ Monitor potassium level and CBC with white cell differential. Check for blood dyscrasias and hypokalemia.
☞ Assess for signs and symptoms of erythema multiforme (sore throat, rash, cough, iris lesions, mouth sores, cough, fever). Report early signs before condition can progress to Stevens-Johnson syndrome.

Patient teaching

• Stress importance of completing entire course of therapy.
☞ Instruct patient to immediately report allergic reactions, rash, or severe diarrhea.
• Instruct patient to contact prescriber if signs and symptoms of infection worsen or if new symptoms develop.
• Advise female patient taking hormonal contraceptives to use alternate birth-control method.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

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penicillin Infectious disease An antibiotic that inhibits crosslinking of peptidoglycan chains in bacterial cell walls; bacteria growing in penicillin synthesize weak cell walls, causing them to burst due to the high osmotic pressure. Cf Ampicillin.