is a combined oral contraceptive that contains two femalehormones estrogen and progestin. This drug is used to preventpregnancy through three main mechanisms. The first mechanism involvesthe prevention of ovulation during the menstrual cycle. The secondmode of action involves preventing the penetration of spermatozoainto the uterus to reach the eggs in the oviduct through thickeningof the vaginal fluid. In the third mechanism, initiatessome changes in the lining of the uterus to prevent attachment offertilized egg. This paper explores various pharmacological aspectsof .
Brand andgeneric names
is abrand name of this combined oral contraceptive. Other brand namesinclude Ortho-Cyclen, Ortho Tri-Cyclen, Orth Tri-Cyclen Lo, andSprintec. The generic name is Norgestimate-Ethinyl Estradiol (ActavisPharma Inc., 2015).
Pharmacokineticsis used to study how a given drug is absorbed into, distributedwithin and eliminated from the body. is administered orallyand swallowed. It is absorbed into the bloodstream through the wallsof the gastrointestinal tract. The drug is composed of norgestimateand ethinyl-estradiol. Most of the drug is absorbed in the smallintestines because it has larger surface area compared to the stomach(Jeske A. H. 2013). is actively absorbed into thecirculation. The metabolites of norgestimate and ethinyl-estradiol(EE) reach their highest plasma concentrations within a period notmore than 2 hours. The drug attains its steady-state plasmaconcentration by the seventh day of every dosing cycle.
Distribution isreferred to as the process by which drug metabolites are transportedto their target cells through the circulatory system. Thedistribution of drug metabolites is affected by various factors. Inthe case of , distribution is significantly enhanced by itsmolecular size and protein binding ability (Jeske A. H. 2013). Therate of distribution is higher when the molecular size of themetabolites is small like the case of . Norelgestromin andnorgestrel are the metabolites of norgestimate, and they bind toplasma proteins by 97%. Norelgestromin binds to albumin only.Norgestrel mainly binds to sex hormone binding globulin (SHBG) butcan also bind to plasma albumin. The binding of EE to plasma albuminresults in an increase in the plasma concentration of SHBG.Norgestimate undergoes first pass metabolism. Norelgestromin is themain metabolite of norgestimate after the metabolism in the smallintestines (Kennedy, Parker & Lott, 2014). Hepatic metabolismresults in active norgestrel and hydroxylated and conjugatemetabolites. EE is metabolized through hydrolytic and conjugationreactions. The conjugates of EE include glucuronate and sulfateproducts. The metabolites of norgestimate and EE are eliminated fromthe body through renal (45%) and fecal (35%) pathways. Onlymetabolized norgestimate is excreted by the renal pathway.
Pharmacodynamicsis described as the study of the effects of a drug and its mode ofaction in the body. Norgestimate is the synthetic form of the femalesex hormone known as progesterone. The ovary produces progesteroneafter ovulation. Therefore, it prevents subsequent ovulation andinitiates the thickening of the uterus. Fall in the level ofprogesterone in the body when implantation does not take placeinitiates another ovulation. Norgestimate mimics progesterone. When awoman in her productive age takes , norgestimate interfereswith the menstrual cycle by ensuring high concentrations of thesynthetic progesterone. In order to prevent ovulation, norgestimatebinds to progesterone and androgen receptors in the female gonad,mammary glands, hypothalamus and the pituitary glands. The bindinginterferes with the stability of the receptor membrane andinactivates specific hormone-responsive genes in the nucleus. Thisreduces the rate of secretion of the gonadotropin-releasing hormoneby the hypothalamus. Therefore, the release of luteinizing hormone(LH) is slowed down. Low concentration of LH delays maturation andrelease of an ovum.
is usedas oral contraceptives to prevent pregnancy as a method of birthcontrol in women.
Women with thefollowing conditions are not recommended to use due to therisks involved (Grossman et al. 2011):
Displaying thromboembolic conditions
Current or history of cerebral vascular disease
Coronary heart disease
Persistent blood pressure of more than 160mm Hg (systolic) and more than 100 mg Hg diastolic
History of deep vein thromboembolic disorders
Diabetes with vascular involvement
Endometrial carcinoma and known or signs of estrogen-dependent neoplasia
Headaches with focal neurological symptoms
Women who have had major surgery involving prolonged immobilization
Confirmed or suspected breast carcinoma or personal history of breast cancer.
Abnormal genital bleeding
History of cholestatic jaundice or jaundice caused by using pills
Hepatic adenomas or carcinomas
Hypersensitivity to any component of
Confirmed or suspected pregnancy
Acute and chronic hepatocellular disease associated with malfunction of the liver
Smoking at the age of 35 and above
Inherited or acquired hyper-coagulopathies
pillsmay have some side effects on the women who use it. However, theusers of the drug should seek emergency medical assistance when theyexperience any allergic reaction presented in the form of hives,breathing difficulties, and swelling of the face, lips, the tongue orthroat. Common side effects of include:
Nausea and vomiting
Breasts become tender
Loss of scalp hair
The facial skin darkens
May have headaches and become dizzy and nervous
Experience difficulties in vision when wearing contact lenses
Appetite or weight changes
Irregular monthly period
Vaginal discharge and itching
There are casesthat require women to stop using and seek help from adoctor. Users should stop using when they experience any ofthe following conditions:
Signs of stroke such as sudden numbness or body weakness, sudden severe headache, slurred speech, and difficulties in vision and body balance
Blood clot in the lungs which is exhibited by signs such as chest pain, sudden cough, wheezing sound, breathing faster and coughing blood
Symptoms of heart attack
Change in the pattern or severity of migraine headaches
Hand, ankle or feet swelling
A breast lump
Signs of depression
Other adverseeffects of include:
Clotting of blood within blood vessels of the eye
Absence of monthly periods
Bleeding that is not associated with menstrual cycle
Increased levels of triglycerides in the blood
Vaginal inflammation or infection
Pain and sudden loss of vision while moving the eye
Yellowing of the eye or skin caused by bile flow problems
High blood pressure
Musculoskeletal disorders such as muscle spasms, pain in extremity and myalgia
Ovarian cyst, vulvovaginal dryness or suppressed lactation
isassociated with little or no risk of birth defects in women whoinadvertently use it during the early stages of pregnancy. There isno increased risk of having genital or non-genital birth problemswhen women are exposed to low dose of before conceiving orin the early stages of pregnancy. However, the drug is notrecommended for inducing withdrawal bleeding as a way of testingpregnancy or to treat threaten or habitual abortion (ActavisPharmacy, 2015).
Nursing mothersare required to use other methods of birth control until they haveweaned their children. Traces of the components of arepresent in the milk of lactating mothers and they may lead to adverseeffects such as breast enlargement and jaundice on the child. The useof in lactating mothers may result in the decrease in thequality and quantity of breast milk.
is safeand effective for women in their reproductive age as well as inpostpubertal adolescents below and above the age of 16.
The safety andefficacy of this drug have not been confirmed in women at the age ofover 65 years. Furthermore, it is not indicated for women in thispopulation.
The combined oralcontraceptive can be used in treating some gynecologic conditions. may be used in managing irregular menstrual cycles,reducing flow, and controlling dysmenorrhea. Since this combined oralcontraceptive reduces circulating androgens, it can benefit womenwith polycystic ovarian syndrome. The use of the COC may improvepremenstrual symptoms.can also benefit older women whoexperience an ovulatory cycles that are characterized by heavybleeding. It can also help in alleviating other perimenopausalsymptoms (Lynna Y. L. & Joan E. 2012). Other conditions that canbe managed using include endometriosis, hirsutism, andmenorrhagia.
Actavis Pharma Inc. (2015), , retrieved fromhttp://medlibrary.org/lib/rx/meds/-2/on 24 August 2016
Grossman et al. (2011), Contraindications to Combined OralContraceptives Among Over-the-Counter Compared With PrescriptionUsers, Obstetrics and Gynecology, 117(3), 558.
Jeske A. H. (2013), Mosby`s Dental Drug Reference, ElsevierHealth Sciences
Kennedy, B. J., Parker, D., & Lott, R. S. (2014). CapstonePharmacy Review. Burlington, MA: Jones & Bartlett Learning.
Kimble T., Thurman A. & Scharwtz J. (2011), Currently availablecombined oral contraception, Expert Review of Obstetrics &Gynecology, Volume 6, Issue 5
Lynna Y. L. & Joan E. (2012), Maternity Nursing Care,Cengage Learning
PubChem, NORGESTIMATE, retrieved fromhttps://pubchem.ncbi.nlm.nih.gov/compound/norgestimate#section=Topon 21 August 2016