Hormonal contraceptives-emergency contraception

Some medicines may only be sold when certain criteria have been met, for example, when supplying emergency hormonal contraception from a community pharmacy. 

The book deals with the minor illnesses or conditions that can be self-treated with advice and treatment from a pharmacist. Three chapters deal with medicines (Chapter 24, nicotine replacement therapy Chapter 32, emergency hormonal contraception and Chapter 2, simvastatin) that have become available without prescription within the last few years and are not treatments for illnesses but are used prophylactically or preventively. 

The book is organised into 34 chapters, arranged in 10 sections based on body systems (e.g. respiratory) or types of condition (e.g. fungal infections), plus a section dealing with women s conditions that includes a chapter on emergency hormonal contraception (Chapter 32). 

Levonorgestrel is metabolised to inactive substances before it is conjugated, and does not therefore undergo enterohepatic recycling of the active moiety. There is no reason to expect that its efficacy as an emergency contraceptive would be affected by antibacterials that alter gut flora and do not induce liver enzymes. No special precautions are necessary with these antibacterials. However, rifampicin and rifabutin are likely to reduce the efficacy of most forms of hormonal contraceptives, as they induce the metabolism of oestrogens and progestagens, see Hormonal contraceptives + Rifamycins , p. 1001. 

The efficacy of both the progestogen-only and combined emergency hormonal contraceptive is likely to be reduced by enzyme inducers such as rifampicin and some antiepileptics. 

Royal Pharmaceutical Society of Great BritaiiL Practice guidance ai the siqrply of emergency hormonal contraception as a pharmacy medicine. September 2004. Available at htty //www.rpsgb.org/pdfs/ehcguid.pdf (accessed 23/08/07). 

Note that antibacterials that do not induce liver enzymes do not affeet the reliability of the progestogen-only contraceptives, see Progestogen-only contraceptives + Antibacterials, p.l007, or the progestogen-only emergency hormonal contraceptive, see Emergency hormonal contraceptives + Antibacterials , p.977. 

---