(FE) Drugs for Skin & Soft Tissue Infx

Question 1

What are the drugs used for skin rashes?

Answer 1

1) Antihistamines

2) Corticosteroid

Question 2

What drugs are used to treat cellulitis?

Answer 2

1) Antibiotics

Question 3

What drugs are used to treat decubitus ulcers?

Answer 3

1) Antibiotics

Question 4

What is the MOA of antihistamines?

Answer 4

Recap: For rashes/eczema/atopic dermatitis

• Competitive antagonism of histamine-binding to receptors, reduces symptoms of inflammation

Question 5

What are the side effects of antihistamine?

Answer 5

• 1st gen
  ~ More CNS effects
  ~ Muscarinic effects (dry mouth, urinary retention, tachycardia)
  ~ Weight gain
  ~ Postural hypotension
• 2nd gen
  ~ eg Loratadine, fexofenadine

Question 6

What is the MOA of corticosteroids?

Answer 6

Recap: To treat rashes/eczema/atopic dermatitis

• Ease swelling and irritation

Question 7

What are the MOA and side effects of antibiotics used to treat cellulitis?

Answer 7

• Cephalexin (Beta lactam, inhibits cell wall synthesis)
  ~ Well tolerated
  ~ Rash and diarrhoea
  ~ SJS
• Clindamycin (Lincosamide, protein synthesis inhibitor)
  ~ Effective against MRSA
  ~ Anaphylaxis, superinfection, myopathy, pseudomembranous colitis

Question 8

What are the MOA and side effects of TZB?

Answer 8

Recap: To treat decubitus ulcers

1) Beta lactam + oxapenam
- e.g. Piperacillin - tazobactam
- Inhibits transpeptidation
- Well tolerated
- Rash
- SJS

2) 2nd gen Fluoroquinolones
- e.g. Ciproflaxacin
- Inhibits DNA synthesis
- Pain and inflammation at injection site
- Tendon rupture
- Anaphylaxis
- Photosensitivity
- Seizure
- Peripheral neuropathy
- Hepatotoxicity
- Not suitable for elderly or athletes with ruptured tendon

3) Lincosamide (Protein synthesis inhibitor)
- eg Clindamycin
- Anaphylaxis
- Myopathy
- Pseudomembranous colitis

4) Non-beta lactam / Glycopeptide
- e.g. Vancomycin
- Inhibits transglycosylation
- Nephrotoxicity
- Ototoxicity
- Red Man’s syndrome