Ketoconazole

synthetic antifungal drug

used for infections such as  athlete's foot, ringworm, candidiasis (yeast infection or thrush), jock itch.

Ketoconazole is used to treat eumycetoma, the fungal form of mycetoma.

MOA: Ketoconazole is imidazole structured, and interferes with the fungal synthesis of  ergosterol, the main constituent of cell membranes, as well as certain enzymes. It is specific for fungi, as mammalian cell membranes contain no ergosterol.

Sensitive fungi Ketoconazole inhibits growth of  dermatophytes and  yeast species (such as Candida albicans).

Characteristics of Opioid Receptors

mu₁

Agonists : morphine phenylpiperidines

Actions:  analgesia bradycardia sedation

mu₂

Agonists : morphine phenylpiperidines

Actions:  respiratory depression euphoria physical dependence  

delta

Actions:  analgesia-weak,  respiratory depression

kappa

Agonists: ketocyclazocine dynorphin nalbuphine butorphanol

Actions:  analgesia-weak respiratory depression sedation

Sigma

Agonists: pentazocine

Action: dysphoria -delerium hallucinations tachycardia hypertension

epsilon:

Agonists: endorphin

Actions: stress response acupuncture

Carbonic anhydrase inhibitors

Acetazolamide, Dichlorphenamide, Methazolamide, Ethoxzolamide

Mechanism of Action

1.    Carbonic anhydrase (CA) facilitates excretion of H+ and recovery of bicarbonate by the proximal renal tubule and ciliary epithelium of the eye. Sodium is recovered in exchange for H+. 
2.    Inhibitors block CA block sodium recovery. A very mild diuresis is produced (this is really a side effect of their use in glaucoma) because relatively unimportant mechanism for Na recovery and because proximal tubule site means that other sodium recovery mechansims continue to process their normal fraction of the sodium load.
 

Neurolept Anesthesia
An antipsychotic agent such as droperidol plus an opiate analgesic agent such as fentanyl or sufentanil. This latter agent is approximately eight to ten times more potent than fentanyl.

Sulfonylureas

1st generation
tolbutamide
chlorpropamide

2nd generation

glyburide
glimepiride
glipizide

Mechanism

glucose normally triggers insulin release from pancreatic β cells by increasing intracellular ATP
→ closes K+ channels → depolarization → ↑ Ca2+ influx → insulin release

sulfonylureas mimic action of glucose by closing K+ channels in pancreatic β cells 
→ depolarization → ↑ Ca2+ influx → insulin release

its use results in

↓ glucagon release
↑ insulin sensitivity in muscle and liver

Clinical use

type II DM

stimulates release of endogenous insulin 
cannot be used in type I DM due to complete lack of islet function

Toxicity

first generation

disulfiram-like effects
especially chlorpropamide

second generation

hypoglycemia
weight gain

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.