OXYMETAZOLINE
 

It is a directly acting sympathomimetic amine used in symptomatic relief in nasal congestion which increases mucosal secretion.

It is used:
- As a nasal decongestant in allergic rhinitis, with or without the addition of antazoline or sodium chromoglycate. 
- As an ocular decongestant in allergic conjunctivitis.

Compounds like naphazoline and xylometazoline are relatively selective α2 agonists, which on topical application produce local vasoconstriction.

Helicobacter Pylori Agents

  Antimicrobial

• Amoxicillin,

• Clarithromycin,

• Metronidozole

• Tetracycline

 Antisecreteory agents accelerates symptom relief and yield healing (omeprozole)

  Bismuth subsalicylate

Therapy For H. Pylori

  Original

• Tetracycline

• Metronidazole (Flagyl)

• Bismuth subsalicylate

• Given for 14 days

• >90% effective in eradicating microorganisms

 New triple therapy

• Amoxicillin

• Clarithromycin

• Omeprazole (Prilosec)

• Given for 7 days

• >90% effective in eradicating microorganisms

Dual Therapy

  Amoxicillin or clarithromycin

  Omeprazole

  Given for 14 days

  60-80% effective in eradication of H. Pylori

Neurophysiology

Nerve fibers exhibit wide range of sensitivity to nerve blockade-in order of increasing resistance to block are the sensations of pain, cold, warmth, touch, pressure, proprioception and motor function

Nerve Fibers:

Myelinated = faster conducting

Unmyelinated = slower conducting

- Small non-myelinated fibers (C- pain fibers) and smaller myelinated pre-ganglionic B fibers are more readily blocked than are larger myelinated fibers responsible for muscle activity and touch [A-alpha and A-beta].

- Clinically, a person would notice complete lack of sensation to a pinprick, while at the same time still be able to move their fingers.

Glucocorticoids 
Cortisol (hydrocortisone) and its synthetic derivatives 

Mechanism 

↓ the production of leukotrienes and prostaglandins   - inhibits phospholipase A2 , inhibits expression of COX-2 , will also stimulate the bone marrow to produce neutrophils resulting in leukocytosis 

halts inflammatory cascade 

↓ leukocyte migration
↓ capillary permeability
↓ phagocytosis
↓ platelet-activating factor
↓ interleukins (e.g. IL-2)

may trigger apoptosis in dividing and non-dividing cells

used in cancer chemotherapy

Clinical use

anti-inflammatory
immunosuppression
cancer chemotherapy (prednisone most common)
CLL
Hodgkin's lymphomas
part of MOPP regimen
Addison disease
asthma

Toxicity

1) must taper dose to avoid toxicity
2) suppression of ACTH → shock state if abrupt withdrawal - > cortical atrophy, malaise, myalgia, arthralgia, fever
3) iatrogenic Cushing  syndrome ->buffalo hump, moon facies, truncal obesity, muscle weakness and atrophy, thin skin, easy bruising, acne
4) osteoporosis - vertebral fractures, aseptic hip necrosis, ↓ skeletal growth in children 
5) hyperglycemia (diabetes) -due to ↑ gluconeogenesis , glaucoma, cataracts, and other complications can subsequently result
6) ↑ GI acid release -ulcers
7) Na+ retention -> edema, HTN, hypokalemia alkalosis, hypocalcemia
8)↓ wound healing
9) ↑ infections
10) mental status changes
11) cataracts

Tetracycline
Tetracycline is an antibiotic produced by the streptomyces bacterium

Mechanism and Resistance Tetracycline inhibits cell growth by inhibiting translation. It binds to the 30S  ribosomal subunit and prevents the amino-acyl tRNA from binding to the A site of the ribosome. This prevents the addition of amino acids to the elongating peptide chain, preventing synthesis of proteins. The binding is reversible in nature.

Example: Chlortetracycline, oxytetracycline, demethylchlortetracycline, rolitetracycline, limecycline, clomocycline, methacycline, doxycycline, minocycline

Source: Streptomyces spp.; some are also semi-synthetic

Spectrum of activity: Broad-spectrum. Exhibits activity against a wide range of Gram-positive, Gram-negative bacteria, atypical organisms such as chlamydiae, mycoplasmas, rickettsiae and protozoan parasites.

Effect on bacteria: Bacteriostatic

Cells become resistant to tetracyline by at least two mechanisms: efflux and ribosomal protection.

Contraindications Tetracycline use should be avoided during pregnancy and in the very young (less than 6 years) because it will result in permanent staining of teeth causing an unsightly cosmetic result.

Tetracyclines also become dangerous past their expiration dates. While most prescription drugs lose potency after their expiration dates, tetracyclines are known to become toxic over time; expired tetracyclines can cause serious damage to the kidneys.

Miscellaneous: Tetracyclines have also been used for non-antibacterial purposes, having shown properties such as anti-inflammatory activity, immunosuppresion, inhibition of lipase and collagenase activity, and wound healing.

Anesthesia agents

1. Inhalation anesthetics (volatile anesthetics)

- gases : N₂O, xenon

- Fluids (vaporisers)

2. Intravenous anesthetics

- Barbiturans : thiopental

- Others : propofol, etomidat

3. Pain killers

- Opioids: fentanyl, sufentanil, alfentanil, remifentanil, morphine

- Non Steroid Anti Inflamatory Drugs: ketonal, paracetamol

4. Relaxants

- Depolarising : succinilcholine

- Non depolarising : atracurium, cisatracurium, vecuronium, rocuronium

5. adiuvants

-benzodiazepins: midasolam, diazepam