Question 5

Outline  the indications,  contraindications, side effects  and  details of  administration  for benzyl penicillin, ciprofloxacin and cotrimoxazole.

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College Answer

Benzyl penicillin:
Indications: treatment of  infection with presumed susceptible organisms (eg.  Strep pyogenes, clostridium [Gram positive bacilli, Gram positive and Gram negative cocci and spirochaetes]). Prophylaxis of  bacterial  endocarditis  and  orthopaedic  trauma  or  surgery.  Prophyla.xjs after splenectomy.
Contraindications: previous adverse reactions (including  allergies)  to penicillin; infection with
organism not susceptible; high dose with renal dysfunction (CNS toxicity).
Side effects: include sensitivity reactions, superinfection (including pseudomembranous colitis), GI. upset, fitting, fever, interactions with other drugs, physical incompatibilities.
Administration: IV or IM. Reconstituted powder. Adult dose 1.2 to 24g over 24 brs in 4-6 doses.

Ciprofloxacin:
Indications: treatment of infection with presumed susceptible organisms (Gram  positive cocci and
Gram negative  bacilli  including  adjuvant  or  S<?le   use  for  resistant  organisms  [eg.  MRSA. pseudomonas, legionella]).
Contraindications: previous adverse reactions (including allergies) to quinolones (including nalidixic acid), pregnancy, children (?<18 years).
Side effects: include sensitivity reactions, superinfection (including pseudomembranous colitis), tendon rupture (esp. with steroids), Gl  upset, CNS stimulation, interactions with  other drugs (especially via inhibition ofP450 system), haematologic/liver enzyme effects.
Administration: IV - Adult dose 200-300 mg over 60 minutes, every 12 hours. Oral- Adult dose
250-750 mg every 12 hours.

Cotrimoxazole: (sulphamethoxazole + trimethoprim)
Indications: Seldom used as first line therapy in ICU but may be used for treatment of infection with susceptible organisms (Gram  positive cocci and Gram negative bacilli including adjuvant or sole use for resistant organisms [eg. pseudomonas, xanthomonas, pneumocysis]), and pneumocystis pneumonia (HIV, bone marrow transplant).
Contraindications: allergy to sulphonamides or trimetboprin (including allergies), blood dyscrasias,
marked renal or hepatic impairment, megaloblastic bone marrow.
Side effects: include sensitivity reactions (eg. photosensitivity), superinfection (including pseudomembranous colitis), GI upset, CNS effects, interactions with other drugs, haematologic
effects.

Administration: IV- Adult dose  75-100 mg/kg per day ofSMX (15-20 mg/kg!day TMP). m 3 or 4 doses. Oral (tablets or syrup) - Adult dose 800mg/160mg (DS) every  12 hours,  (? daily for prophylaxis).

Discussion

More recently, questions regarding fine detail of pharmacology for such drugs have been abandoned, perhaps reflecting that a vast wealth of such information is available rapidly through online media, and its perpetual storage in the brains of fellows is superfluous.

It does also seem as if some of these questions have migrated into the CICM Part I curriculum, where one might reasonably be expected to answer questions about basic pharmacology of common ICU drugs. The domain of fellowship seems to be more related to the validity of indications for the use of drugs, the interpretation of evidence behind broad trends in ICU management. These days, the candidate won't be expected to discuss the pharmacology of levosimendan; they will be asked to critically evaluate its use as a general vitality-enhancing tonic.  

Anyway. One can only tabulate the answer when the college answer is that good.

Features

Benzylpenicillin

Cotrimoxazole

Ciprofloxacin

Indications

Treatment of susceptible gram-positive organisms

Treatment of susceptible gram-positive and gram-negative organisms, including comminuty-acquired MRSA and PJP

Treatment of susceptible gram-positive and gram-negative  organisms

contraindications

Hypersensitivity to penicillin

Hypersensitivity to sulfonamides
Blood dyscrasias

Hypersensitivity to quinolones
pregnancy

side effects

Selection for resistant organisms
Gastrointestinal effects due to changes in gut flora

Selection for resistant organisms
Gastrointestinal effects due to changes in gut flora

Selection for resistant organisms
Gastrointestinal effects due to changes in gut flora
Tendon rupture
Interaction with other drugs

details of administration

1.2-2.4 g q4h

75-100/15-20 mg/kg/day in 3-4 divided doses

200-300mg tds