ointment

• Ointments


  Homogeneous, semi-solid preparations intended for external application to the skin or mucous membranes
• Ointments


  • Used as emollients or for the application of active ingredients to the skin for protective, therapeutic, or prophylactic purposes and where a degree of occlusion is desired
  • Formulated using hydrophobic, hydrophilic, or water-emulsifying bases to provide preparations that are immiscible, miscible, or emulsifiable with skin secretions
  • Can be derived from hydrocarbon (fatty), absorption, water-removable, or water-soluble bases
• Classification of ointment bases

  • Oleaginous
  • Absorption
  • Emulsion
  • Water-soluble
• Oleaginous ointment bases


  Include vegetable oils, animal fats, and hydrocarbons derived from petroleum
• Oleaginous ointment bases


  • Become rancid and foul smelling on exposure to atmosphere and light, so preservatives and antioxidants are necessary
  • Petrolatum-type bases are more stable than vegetable- or animal-type bases
  • Able to absorb only very small amounts of water, unless treated with cholesterol
  • Highly compatible; all but the fats and oils are stable; good emollients
  • Difficult to remove from skin and clothing; uncertain as to yield of medicament
• Absorption bases


  Anhydrous (waterless), hydrophilic (water loving) bases that absorb water or aqueous solutions of medicinal
• Absorption bases


  • Hydropholic Petrolatum, USP
  • Aquaphor
• Absorption bases


  • Anhydrous; will absorb water; most are not washable
  • Highly compatible; relatively stable to heat; can be used in anhydrous form or water can be added when emolliency is desired
  • Greasy
• Emulsion bases


  Consist of an aqueous phase, an oleaginous phase, and an emulsifying agent; true, solid emulsions
• Emulsion bases


  • Lanolin, USP (w/o)
  • Hydrophilic Ointment, USP (o/w)
  • Vanishing creams (o/w)
• Emulsion bases


  • The w/o emulsion bases are insoluble in water and are not washable; the o/w emulsion bases are washable and nongreasy
  • Washable and nongreasy if oil-in-water (o/w)
  • Subject to water loss if o/w, greasy and unwashable if water-in-oil (w/o), unless a preservative is added, the emulsion bases are subject to mold growth
• Water-soluble bases


  The polyethylene glycol polymers, or Carbowaxes, are of great importance in ointments
• Water-soluble bases


  • Polyethylene Glycol Ointment, USP
  • Water-soluble ointment base
  • Bases containing pectin, cellulose, bentonite, and gelatin
• Water-soluble bases


  • Anhydrous, but will absorb water and dissolve in water; washable; nongreasy
  • Wide range of compatibility; do not become rancid or support microbial growth; nonirritating; adhere well to skin; easily washed off; low incidence of sensitization
  • Sometimes undergo gradual discoloration with certain drugs; unless cetyl alcohol is added, an aqueous solution can be added only to the extent of 5 percent
• Preparation of ointments


  1. Incorporation method

  2. Fusion method
• Combined oral contraceptive pill (COCP)

  A birth control method that includes a combination of an estrogen (estradiol) and a progestogen (progestin)
• COCP


  • When taken by mouth every day, these pills inhibit female fertility
  • Hormones control the ovaries and the uterus
• Mechanism of action of COCP

  1. Progestogen negative feedback decreases the pulse frequency of gonadotropin-releasing hormone (GnRH) release, which decreases the release of follicle-stimulating hormone (FSH) and greatly decreases the release of luteinizing hormone (LH)

  2. Decreased levels of FSH inhibit follicular development, preventing an increase in estradiol levels

  3. Progestogen negative feedback and the lack of estrogen positive feedback on LH release prevent a mid-cycle LH surge

  4. Inhibition of follicular development and the absence of a LH surge prevent ovulation

  5. Estrogen negative feedback on the anterior pituitary greatly decreases the release of FSH, which inhibits follicular development and helps prevent ovulation

  6. Inhibition of sperm penetration through the cervix into the upper genital tract by decreasing the amount of and increasing the viscosity of the cervical mucus
• The primary mechanisms of action are so effective that the possibility of fertilization during COCP use is very small