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Query: UMLS:C0020473 (hyperlipidemia)
 15,891 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Low dose estrogen tablets, containing less than 50 mcg of ethinyl estradiol, were formulated because of the recognized dose response relationship with the steroid content of the tablet and side effects. These new oral contraceptives (OCs) are as effective as the older high-dose OCs, and available evidence reports fewer side effects. This discussion reviews pharmacology of these new OCs, the mechanism of action, contraindications, side effects, and problems with the low-dose estrogen OC. Ethinyl estradiol is the only estrogen used in the low-dose combination OC. There are several synthetic progestins: norethindrone, norethindrone acetate, norgestrel, levonorgestrel, and ethynodiol diacetate. These progestins have different potencies so the pharmacologic activity cannot be accurately predicted based on the amount present in the tablet. The synthetic steroids in OCs are absorbed in the small intestine, metabolized in the liver, excreted in the bile and feces with a half-life of 24 hours. The low-dose estrogen combination preparation is taken 3 out of every 4 weeks. Its contraceptive effect is primarily a result of hypothalamic mediated gonadotropin suppression with subsequent inhibition of ovulation. Contraindications to taking the low-dose OC are the same as for the higher dose OC: thromboembolic or cardiovascular disease, estrogen dependent neoplasia, markedly impaired liver function, undiagnosed genital bleeding, congenital hyperlipidemia, pregnancy, and women over age 30 who smoke. Relative contraindications include hypertension, diabetes mellitus, migraine headaches, uterine myomas, and epilepsy. The often quoted 2-5-fold increased incidence of thromboembolic disease, myocardial infarction, and stroke is based on large epidemiologic studies involving patients taking the older higher dose OCs. Current data from patients taking the newer low-dose medication demonstrate minimal if any increased incidence of these problems in young women who do not smoke. The low-dose estrogen OCs have minimal effect on lipid levels. Early reports of patients using the low-dose OC have shown little if any increased incidence of hypertension. The low-dose contraceptives have little effect on glucose tolerance, and there is no evidence to show an increased incidence of overt diabetes in OC users. There is no evidence that use of the combination OC causes an increase in cancer of the cervix, uterus, or ovaries. Clinical complaints of nausea, breast discomfort, chloasma, weight changes, and depression are reduced with the low-dose estrogen preparation. Hypomenorrhea while taking the OC occasionally occurs because the lower dose of estrogen is insufficient to stimulate the endometrial growth in face of the predominant progestin-atrophy effect.
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PMID:Oral contraceptives in 1984. 649 Mar 38

Epidemiological studies clearly indicate that combined oral contraceptives (OCs) increase risks of vascular thromboses. The risk of myocardial infarct is increased by 3 for combined OC users aged 30-39 and by 5 for those aged 40-44. Risks of deep phlebitis and cerebral thromboses are also 5 times greater in OC users. The effects of OCs on serum lipid levels depend on the dose and type of estrogens and progestin. Ethinyl estradiol causes an increase in triglycerides and HDL cholesterol, while progestins tend to increase total cholesterol and decrease HDL cholesterol. Low-dose combined OCs have slight or no effect on cholesterol, HDL cholesterol or triglycerides. Moderately dosed combined OCs elevate triglycerides but their effects on total cholesterol and HDL are moderate. High dose combined OCs increase triglyceride and cholesterol levels. The combined effects of the estrogen and progestin in high dose pills usually increase HDL cholesterol, but there is some doubt as to whether the increase is beneficial. Although all combined OCs have deleterious effects on serum lipids, only persons predisposed to hyperlipidemia are truly at risk. Young women using OCs require systematic control, of serum lipid and lipoprotein levels. Low-dose formulations are generally preferable. Standard or high dosed OCs can cause disturbances of glucose metabolism in predisposed women, but risks of patent diabetes are small. Glucose intolerance developed during pill use is not always reversible. The risk appears more serious with pills containing estranes or norgestrel than with those containing pregnanes. Low-dose pills entail less deterioration than higher dosed pills. Low-dose progestin-only pills also have deleterious effects. OCs interfere with glucose metabolism in part by creating an effect of peripheral insulin resistance and in part by diminishing the insulin-secreting capacities of the islets of Langerhans. All OCs are contraindicated in women with histories of gestational diabetes or glucose intolerance. Insulin-dependent diabetes in adolescents is a relative contraindication. Regular surveillance is required of weight and blood sugar for normal women using OCs. Estrogens have been the major factor identified in variations of coagulation factors and fibrinolysis in OC users. Platelet aggregation has been less well studied. OCs should be avoided in case of hypercoagulative states of platelet hyperaggregation.
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PMID:[Metabolic risks of oral contraception]. 1228 76