Pharmacology

Question 1

Flucloxacillin IV

Answer 1

Indications:

• Treatment of confirmed or suspected staphylococcal infections and other Gram positive coccal infections
• Pneumonia, skin and skin structure and wound infections, infected burns and cellulitis

Contraindications:
- Hypersensitivity to penicillins, cephalosporins and multiple allergens

Adverse reactions:

• Hepatitis and cholestatic jaundice
• Nausea, vomiting, diarrhoea, dyspepsia, constipation, abdominal pain, heartburn and loss of appetite
• Bronchospasm

Dosage:
Usual adult dosage. Intravenous injection/ infusion. 250 mg to 1 g 6 hourly.

Question 2

Cefaclor

Answer 2

Indications:

• Treatment of the following types of infection
• Acute bronchitis and acute exacerbations of chronic bronchitis.
• Upper respiratory infections, including pharyngitis, tonsillitis and acute bacterial sinusitis.
• Community acquired pneumonia of mild to moderate severity (excluding atypical pneumonia).
• Symptomatic lower urinary tract infections, including cystitis.
• Skin and skin structure infections.

Contraindications:
- Known allergy to the cephalosporin group of antibiotics; previous major allergy to penicillin

Adverse Reactions:

• Diarrhoea
• Nausea and Vomiting
• Rash/urticaria

Dosage and Administration
- (PO) The usual adult dosage is 375 mg twice daily.

Question 3

Paracetamol (oral)

Answer 3

Analgesic, Antipyretic
Inhibits prostaglandin synthesis in the CNS
Peaks 20-120 mins average 51mins
Half life 6 hrs

Contraindications:
Other paracetamol containing drugs

Reactions:
Rare
Allergic reactions
Dyspepsia
Nausea
haematological

Dosage:
Adults – 1G every 4 hours (Maximum daily dose of 4G)
Children – 15mg/KG (max 60 - 90mg/kg/day)

Question 4

Atenolol

Answer 4

Hypertension, angina, cardiac arrythmias, MI
beta-adrenoreceptor blocking drug which acts preferentially on beta-receptors in the heart.

Contraindications:
Bronchospasm
CCF
Allergic disorders
Hypotension
Sick Sinus Syndrome
Shock

Reactions:
constipation
Nausea
Dry mouth
Bradycardia
Postural hypotension
Raynauds

Dosage:
Adults – Initiated 50mg daily, increased to a maximum of 200mgs daily (dose dependant on patients needs/alleviation of symptoms)

Question 5

Flecainide (PO)

Answer 5

Supraventicular arrythmias, Paroxysmal atrial fibrillation/flutter
Peak plasma drug levels are attained at about 3 hours

Contraindications:
Second or third degree A-V block
Right bundle branch block
Cardiogenic shock.
Known hypersensitivity to the drug.

Reactions:
Fatigue
Palpitations
Constipation
Tremor
Bradycrdia
Anxiety
Tinnitus

Dosage:
Adults – Initiated 50mg twice daily, increased to a maximum of 400mgs daily (dose dependant on patients needs/alleviation of symptoms)

Question 6

Heparin Infusion

Answer 6

Anticoagulant, antithrombolic
Following IV injection – effective for 3-6hrs

Contraindications:
Not for IMI
Hypersensitivity to heparin or Pork products
History of heparin induced thrombocytopenia
Reactions
Haemorrhage
Thrombocytopenia
Skin necrosis at injection site
Hypersensitivity
Long term use reactions are varied (see MIMS)

Dosage:
Treatment of established venous thrombosis or pulmonary embolism. The following regimens may be followed.(i) Continuous intravenous infusion. A bolus dose of 5,000 IU may be given initially followed by an infusion of 20,000 to 40,000 IU in 1 L of sodium chloride injection 0.9% or in any other compatible solution over 24 hours.(ii) Intermittent intravenous injection. An initial dose of 10,000 IU either undiluted or in 50 to 100 mL sodium chloride injection 0.9% followed by 5,000 to 10,000 IU every four to six hours.(iii) Deep subcutaneous injection. A different site should be used for each injection to prevent the development of massive haematoma. Usual dose is 5,000 IU injected intravenously followed by a subcutaneous injection of 10,000 IU every eight hours or 15,000 IU every 12 hours