CEPHALOSPORINS

CEPHALOSPORINS- INTRODUCTION

• Cephalosporin discovery credited to Brotzu in 1945 in sewer water off coast of Sardinia
• Several compounds isolated from mold Acremonium chrysogenum as basic nucleus for future drugs
• First introduced into clinical use in 1964 (cephalosporin)

DEFINITION

• Cephalosporins are beta-lactam antimicrobials with bactericidal activity used to manage a wide range of infections from gram-positive bacteria.
• The Cephalosporins are structurally related to the penicillin’s chemical groups but have a varying pharmacologic properties and antimicrobial activities.

CLASSIFICATION OF CEPHALOSPORINS

First generation cephalosporins: These are group  of  cephalosporin which act against staphylococcal infection.

Example:

• Cephazolin sodium Dosage 500mg to 1gm, route IM or IV.
• Cephadrine: Dosage 125 to 250 mg, route IM or IV.
• Cephalexin: dosage 125,  250,  500  mg  per  oral  capsules.

Second generation cephalosporins: These are antibiotics which act against staphylococcus and some of the gram negative micro organism.

Example:

• Cefuroxime: Tab 250 mg to 1.5 gm, syrup 25 mg per ml per oral route, Inj. 250 to 1 gm IM or IV.
• Cefemandole: Inj.1 to 2 gm IV

Third generation cephalosporins: These are antibiotics which are effective against gram negative micro organisms and  has no effect on staphylococcal infection.

Example:

• Cefotaxime: Inj.1to 2gm IV or IM.
• Cefatizidime: Inj.250, 500, 1000mg IV or IM.
• Ceftriaxone: Inj. 125 to 1 gm IM or IV.

Fourth generation cephalosporins: These are Cephalosporins with bactericidal action. They exert greater anti bacterial effects than other Cephalosporins.

Example:

• Cefepime: Inj. 200 to 400 mg IV or IM
• Cefiprome: Inj. 500mg IV or IM

Fifth generation cephalosporins: These are advanced generation cephalosporin active against methicillin- resistant Staphylococcus aureus (MRSA) and Gram-positive bacteria. It retains the activity of later-generation cephalosporins having broad spectrum activity against gram negative bacteria.

Example:

• Ceftaroline fosamil (teflaro) 600mg IV
• Zerbaxa (ceftolozane and tazobactam) 1.5 gm IV

MECHANISM OF ACTION OF CEPHALOSPORINS

Cephalosporins act by penetrating in to the bacterial cell  wall

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They bind with the proteins in the cell wall & block them

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causes Instability of the bacterial cell wall

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  Inhibits the multiplication of cells and cell wall synthesis

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Bacteria loses its potency

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Death of micro organism.

DRUG INTERACTION OF CEPHALOSPORINS

• The drug reacts when taken with alcohol
• Exhibits toxic effects when administered with aminoglycosides
• Decreases the effect of drugs like erythromycin and chloramphenicol.

PHARMACOKINETICS OF CEPHALOSPORINS

• Oral absorption of drug is poor.
• Most Cephalosporins can only be administered parenterally.
• When injected Intravenously the drug remains in circulation for 8 to 12 hrs.
• Cephalosporins are eliminated mostly by the kidneys, some with a substantial contribution  from active tubular secretion.
• Only a few cephalosporins have a high biliary elimination.

INDICATIONS OF CEPHALOSPORINS

• Tonsillitis
• Respiratory infections
• Otitis Media
• Septicemia
• Urinary tract Infection
• Bone and joint infection
• GI infections
• Meningitis
• Skin and soft tissue infections
• Strep throat
• Sinus infections
• Gonorrhea
• Lyme disease
• Methicillin Resistant staphylococcus aureus

CONTRAINDICATIONS OF CEPHALOSPORINS

• Pregnancy
• Lactation
• Renal disease
• Hypersensitivity/ allergic to penicillin
• Toxic Effects
• Renal toxicity
• Ototoxicity

ADVERSE & SIDE-EFFECTS OF CEPHALOSPORINS

• Joint Pain, weakness & fatigue
• Dyspnea  & swelling in the tongue & throat
• fever & chills
• Abdominal pain, Anorexia, nausea, vomiting & diarrhea
• Thrombocytopenia, eosinophilia, anemia & leucopenia
• urticaria, rash & paresthesia
• Hypersensitivity Reaction

NURSING RESPONSIBILITY IN ADMINISTERING THE DRUG

• Assess sensitivity to Cephalosporins by administering test dose
• Monitor vital signs
• Maintain intake output chart
• Monitor the skin for rash and allergic reactions
• Monitor for any changes in the tongue & throat and withdraw the drug if there is swelling
• Monitor the breathing pattern of the client & Administer Oxygen therapy, if needed
• Monitor Blood studies CBC, RFT, LFT before administration of the drug to identify toxicity
• Perform ear examinations and inform the client about the adverse effect and notify the physician if there is any signs of toxicity like hard of hearing, tinnitus, vertigo etc.
• Monitor for any signs of bleeding after drug administration
• Dilute the drug in 20 to 100 ml solution before administration to prevent thrombophlebitis
• Advise the patient to avoid alcohol
• Monitor for GI disturbances
• Administer the drug in caution for patients with seizure disorder and for clients on Anti-coagulants
• Evaluate therapeutic response treatment of infection.