Routes of Drug Administration PDF

# Routes of drug administration ## Faculty of Veterinary Medicine Department of Pharmacology Pharmacology - 3^th Level Students ### Routes of drug administration - Sublingual - Parenteral: IV, IM, SC - Inhalation - Oral - Transdermal patch - Rectal - Topical # Factors af...

# Routes of drug administration ## Faculty of Veterinary Medicine Department of Pharmacology Pharmacology - 3^th Level Students ### Routes of drug administration - Sublingual - Parenteral: IV, IM, SC - Inhalation - Oral - Transdermal patch - Rectal - Topical # Factors affecting the choice of route of administration: 1. Form of drug 2. Physical & chemical properties of drug. 3. Rapidity of response 4. Behavioral characteristics of animal 5. Nature and location of the disease # Routes of Drug Administration - Body orifices - Oral - Nasal - Respiratory - Rectal - Vaginal - Urethral - Intramammary - Parental - IV - IM - SC - Intracardiac - Intra-articular - Epidural - Topical (local # A) BODY ORIFICES: - Oral Route (by mouth=Per Os): - Drug which is given orally should be: 1. Palatable 2. Non-irritant 3. Stable at intestinal and gastric pH 4. Unaffected by digestive juice 5. Adequately absorbed - Advantages: 1. Convenient 2. Economic and cheap 3. Variety (forms) 4. Safe - Disadvantages: 1. Difficult handling 2. Can't use in unconsious animals 3. Can't use in emergency 4. Unsuitable in Gastrointestinal Tract disturbance 5. Some drugs are irritant 6. Some drugs are destroyed by gastric acidity 7. Some drugs are destroyed by gastric enzyme 8. Some drugs are decomposed in large Gastrointestinal Tract # 2) Nasal m.m: - Nasal drops - nasal m.m - local effect - Ex: anti-inflammatory drops - ttt rhinitis - Nasal decongestant drops - vasoconstriction - 3) Respiratory m.m (inhalation): - Drug is given in the inspired air - Forms: gas (No), volatile liquid (ether), aerosol (isoprenaline spray) - Used: - Local effect: bronchodilator for ttt asthma - Systemic effect: general anesthesia - Advantages: Rapid onset of action # 4) Rectal Route (Per rectum): - Drug forms: suppositories or Enema - Uses: - Local effect: purgative, evacuate intestine. &ttt enteritis & piles - Systemic effect: suppositories of antibiotics - N.B: usually absorption is slow from rectal mucosa so it's used when the oral route is unsatisfactory # 5) - Vaginal route: - Drug forms: pessaries & Uterine tablets - Uses: Local ttt: vaginal & uterine affections # 6) Urethral route: - Drug given by: catheter - Uses: Local ttt: urethra, prostate and urinary bladder affections # 7) Intramammary: - Drug given by: teat catheter(syphon) or cannula (udder infusion) - Uses: Local ttt: udder affections (mastitis) # B) Parental (By Injection): - Injection: introducing the drug into the body by means of syringes into the required site - Injection used in the following conditions (advantages): 1. Drug is non-effective orally - Destruction by gastric acidity - penicillin or by enzyme - insulin - Failure of intestinal absorption - streptomycin 2. Drug has irritant action - nausea and vomiting 3. In Gastrointestinal Tract disturbance 4. In unconscious animal 5. In Emergency 6. Necessary to rapidly raise concentration of drug in the body # 1) Intravenous (I/V) - Inject in superficial vein: - Horse, cattle, ruminant - jugular vein - Dog & cat - cephalic & saphenous vein - Pig & rabbit - ear vein - Poultry - wing vein - N.B: most rapid onset and short duration of action - I/V injection: must be very slowly injected - to avoid toxic & allergic effect - Uses: - Emergency - Irritant drug to tissue (diluting effect of blood) - Large dose (I/V infusion ) # 2) Intramuscular (I/M) - Vertically deep in skeletal muscle - Gluteal - Upper thigh - N.B: slower absorption and longer duration of action than I/V - Onset of action can be fastened by H₂O vehicle or lowered by oil vehicle - Uses: Moderate irritant - muscle less sensitive to pain # 3) Subcutaneous (hypodermic) (S/C) - Under skin - loose - neck, axillary, and inguinal fold of skin - N.B: slower absorption and slightly longer duration of action than I/M - Uses: - Non irritant drug (avoid local tissue damage) - Non hyper-osmotic (edema) # 4) Intradermal (I/d) - Into skin - Uses: - Diagnostic tests as tuberculin test for tuberculosis diagnosis - Allergic test as penicillin # 5) Intraperitoneal (I/P): - Inject drug into abdominal cavity - N.B: used for very rapid absorption of drug when I/V and other routes are not available (used especially in lab animals ) # 6) Intra-cardiac: - Inject drug through chest wall into heart - Uses: Emergency (cardiac arrest) # 7) Intra- articular: - Inject drug directly into synovial fluid (joint capsule) under highly sterilize environment. - Uses: Joint inflammation # 8) Epidural: - Inject local anesthetic agent in the epidural space inside the spinal canal outside dura matter - Uses: For regional anesthesia # c) Topical (local): - Drug placed on the skin or mucous membrane - Uses: - Local effect: counter irritant, anti-inflammatory, antiseptic - Systemic effect: after absorption, through skin (rarely) - N.B: drugs are absorbed more slowly through skin than other body membranes, but the rate of absorption can increase by placing drug in a vehicle.