Oral contraceptives products available

L-Fohc acid is available as a crystalline dihydrate containing 8% water. Approximately 80% of the commercial production is consumed for feed enrichment in animal nutrition. FoHc acid is being offered by the pharmaceutical industry for therapeutic and prophylactic use (see Pharmaceuticals). Pharmacological doses of fohc acid are commonly used as a rescue dose during cancer chemotherapy, in women using oral contraceptives, and alcohoHcs. Several studies have provided evidence that multivitamins or foHc acid (0.8—4 mg/day) supplementation prevent the majority of neural tube defects (101). 

As indicated earlier, plant products can be useful as starting materials for the semisynthetic preparation of other drugs. An important example in this regard is the Mexican yam, which produces a steroid precursor (diosgenin) vital to the synthesis of steroidal hormones used in oral contraceptives (i.e., progesterone). The availability of diosgenin eliminates numerous expensive steps in the organic synthesis of the basic steroid molecule. It was this discovery that contributed to the development of the pharmaceutical company Syntex (now a subsidiary of Hoffman LaRoche) and the development of the first birth control pill. 

In 1960 Searle became the first to introduce an FDA-approved oral contraceptive. Early in 1962 Johnson Johnson s subsidiary. Ortho Pharmaceuticals, debuted its Norethindrone-based pill in 1964 Parke Davis and Syntex (with Eli Lilly) announced their FDA-approved products. Thus in the United States three of the first oral contraceptives that became available were developed by Syntex or manufactured from materials it produced. 

POSTCOITAL OR EMERGENCY CONTRACEPTIVES The FDA has approved two preparations for postcoital contraception. PLAN-B is two doses of the minipiU (0.75 mg levonorgestrel per pdl) separated by 12 hours PLAN-B will soon be available without a prescription for women 18 years old and older, preven is two 2-pill doses of a high-dose oral contraceptive (0.25 mg of levonorgestrel and 0.05 mg of ethinyl estradiol per pUl) separated by 12 hours. The FDA also has declared other products with the same or very similar composition safe and effective for use as emergency contraceptive piUs. 

There have been many developments in formulations used for oral contraceptives since the original studies. Nowadays, there are numerous products available such... 

Aerosols. Pressurized containers to deHver aerosolized dmg products through appropriate systems of valves and actuators have been available since the 1950s (see Aerosols). Such dosage forms are used as external appHcations of lotions and creams, for oral inhalation, or for treatment of the vaginal cavity, eg, contraceptive foams. Aerosols contain two- or three-phase systems, wherein a volatile Hquid or admixture of Hquids is sealed in a... 

The chronic administration of molecules, which have a short biological half-life and cannot be given orally, presents a difficult challenge to formulators. One strategy which might be considered is the development of a sustained-release intramuscular or subcutaneous injection. Other non-parenteral options could include the inhalation or intranasal route, both of which have their own unique challenges. Sustained-release parenteral formulations might also be required in circumstances where patient compliance is likely to be poor. This consideration has led to the development of some antipsychotics and contraceptives as sustained-release injections. Table 9.6 lists some of the sustained-release parenteral products which are available on the U.S. market and their respective formulations. The typical approaches used in the formulation of sustained-release parenterals are summarised in this section. 

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