Medication

Medication used at AMAC includes:
Anti-D
Fentanyl
Misoprostol
Mifegyne

 

Anti-D Injections and Rhesus negative women

Rh (Rhesus) is a blood group on the red blood cells of some people. Most people have the Rhesus factor and are classed as Rh positive (+ve) but if you do not have the Rhesus factor you are classed Rhesus negative (Rh –ve).

Approximately one in seven Europeans are Rh –ve whereas only one in forty people of Maori, Polynesian and Asian descent are negative. These differences are normal just like different hair and eye colour.

If you are Rh –ve and pregnant with a foetus that is Rh +ve you might make Anti-D which is an antibody that reacts with Rh blood group factor. This happens as a result of Rh +ve blood cells from the foetus entering into the mothers blood stream. Antibodies are produced by the mothers immune system to destroy the Rh +ve red blood cells in the mothers blood. These antibodies can stay in the mothers’ blood stream for many years. If the next pregnancy is RH –ve the antibodies in the mothers’ blood stream can attack the red bloods cells of the foetus, which can lead to haemolytic disease of the newborn.

If a women does not have an Anti-D injection after having a Rh positive pregnancy the chances that she will make Anti-D is about 1 chance in 12. If a women has the Anti-D injection the chances of making Anti-D is almost zero.

The Anti-D injection must be offered to Rh-ve mothers within 72 hours of birth of a Rh +ve baby, miscarriage, abortion or injury to the abdomen during pregnancy. This injection destroys any red blood cells that may have transferred into the mothers blood from the foetus and in most women will prevent women from making Anti-D.

As with all treatments, you have the right to decide whether you want to have the treatment or not. It is important that you realise that if you choose not to have the injection and make Anti-D in your blood it could cause any future babies to become anaemic before the birth causing jaundice to the baby which can vary from very mild to severe and life threatening for that baby.

A brochure from the New Zealand Blood Services will be provided for you to read at AMAC which fully explains details of Rh factor and Anti-D injections, the benefits and risks to yourself and any future pregnancies. The doctors will answer any questions you may have before asking you to sign consent or refusal of the injection.

A data sheet on Anti-D is also available at http://www.medsafe.govt.nz/DatasheetPage.htm

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Fentanyl

Name: Fentanyl Citrate ivi & imi

Action: Potent narcotic analgesic with a rapid onset and short duration of action. The principle actions of therapeutic value are analgesia and sedation. The action is similar to morphine and pethedine but Fentanyl differs by its short duration of analgesic activity, lack of emetic activity and minimal hypotensive activity.

Uses: Analgesic action of short duration during maintenance in general or regional anaesthesia.

Doses and administration: Adjunct to regional anaesthetic 50-100mcg IMI or slow IV.

Contra indications . Patients suffering with bronchial asthma.

Intolerance to morphinomimetics, susceptibility to respiratory depression e.g. head injuries, brain tumours, children<2 yearsMAOI’s (+/- 14 days).

Precautions: Chronic opioid therapy: history of opioid abuse:

Abuse potential: pulmonary impairment: decreased respiratory reserve, rapid injection: alcoholism, real hepatic impairment: pregnancy, lactation (within 24 hours of admin).

Use in pregnancy: Category C classification-indicates pharmacological effects have caused or may be suspected of causing harmful effects on the human foetus or neonate without causing malformation. When given in high doses in late pregnancy phenothiazines have caused prolonged neurological disturbances in the infant.

Adverse reactions: Most common is respiratory depression - can be reversed by naloxone, apnoea, muscle rigidity, nonepileptic myoclonic movements, bradycardia, hypotention.

Interactions: CNS depressants including neuroleptics, general anaesthetics, alcohol, barbiturates, benzodiazepines; MAOIs; ritonavir; CYP3A4 inhibitors.

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Misoprostol

 

Before your abortion, the doctor will offer you two tablets to take called MISOPROSTOL.

In New Zealand, medicines are registered for a specific purpose. Misoprostol has been used safely in New Zealand for many years as a medicine for the treatment of stomach ulcers and is registered for that purpose rather than to help with abortions.

Even though Misoprostol is not registered to be used in abortion, research has shown that it is sufficiently safe and effective and we believe helpful before your abortion.

Advantages of using Misoprostol before your abortion:

Side effects are rare, but using Misoprostol before your abortion may result in:

It is important that you treat the taking of Misoprostol tablets as the start of your procedure. This is because once taken they will soften and relax your cervix. You would have the risk of miscarriage occurring, heavy bleeding or foetal abnormality if you change your mind about the abortion after taking the tablets.

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Mifegyne

Mifepristone micronised 200 mg

Active substance Mifepristone micronised 200 mg
Excipients or other ingredients (all of mineral or vegetable origin):

Presentation:

Light yellow, cylindrical, bi-convex tablets, for oral administration. Blister pack (PVC and aluminium foil and carton) containing 3 tablets of Mifegyne 200 mg. Medicines classification: Prescription medicine.

Uses:

Actions: Mifepristone is a synthetic steroid with an antiprogestational action as a result of competition with progesterone at the progesterone receptors. In women at doses of greater than or equal to 1mg/kg, mifepristone antagonises the endometrial and myometrial effects of progesterone. In pregnancy it sensitises the myometrium to the contraction-inducing action of prostaglandin. It is an abortifacient. It does not bind to mineralocorticoid receptors; therefore the risk of acute adrenal failure during mifepristone intake is negligible. It binds to the glucocorticoid receptors. In animals at doses of 10-25 mg/kg it inhibits the action of dexamethasone. In man the antiglucocorticoid action is manifested at a dose equal to or greater than 4.5 mg/kg by a compensatory elevation of ACTH and cortisol.

It has a weak anti-androgenic action which only appears in animals during prolonged administration of very high doses.

Pharmacokinetics: After oral administration of a single dose of 600 mg, mifepristone is rapidly absorbed. The peak concentration of 1.98 mg/ml is reached after 1.3 hrs (mean of 10 subjects). There is a non-linear dose response. After a distribution phase, elimination is at first slow, the concentration decreasing by a half between about 12 and 72 hrs and then more rapidly, giving an elimination half-life of 18 hrs. With radio receptor assay techniques, the terminal half-life is up to 90 hrs, including all metabolites of mifepristone able to bind to progesterone receptors. After administration of low doses of mifepristone (20 mg orally or intravenously) the absolute bioavailability is 69%. In plasma, mifepristone is 98% bound to plasma proteins: albumen and principally alpha-1-acid glycoprotein (AAG), to which binding is saturable.

Due to this specific binding, volume of distribution and plasma clearance of mifepristone are inversely proportional to the plasma concentration of AAG. N-Demethylation and terminal hydroxylation of the 17-propynyl chain are primary metabolic pathways of hepatic oxidative metabolism.

After administration of a 600 mg labelled dose of mifepristone, 10% of the total radioactivity is eliminated in the urine and 90% in the faeces. Mifepristone is a lipophilic compound and may theoretically be excreted in the mother's breast milk.

Indications:

  1. As a medical alternative to surgical termination of intra-uterine pregnancy
  2. Softening and dilatation of the cervix uteri prior to surgical pregnancy termination
  3. Preparation for the action of prostaglandin analogues in the termination of pregnancy for medical reasons
  4. Labour induction for the expulsion of a dead foetus (foetal death in utero).
Dosage and administration

There are no precautions for timing in relation to food.

As a medical alternative to surgical termination of intra-uterine pregnancy in early pregnancy: 600 mg mifepristone (3 tablets) in a single oral dose followed 36-48 hrs later, by the administration of a prostaglandin analogue; misoprostol 400 mcg orally (up to 49 days) or gemeprost 1 mg vaginally (up to 63 days).

Softening and dilatation of the cervix uteri prior to surgical pregnancy termination: 200 mg mifepristone (one tablet), followed 36-48 hrs later (but not beyond) by a surgical termination of pregnancy.

Preparation for the action of prostaglandin analogues in the termination of pregnancy for medical reasons (to reduce the doses of prostaglandin): 600 mg of mifepristone (3 tablets) taken in a single oral dose, 36-48 hrs prior to scheduled prostaglandin administration which will be repeated as often as indicated.

Labour induction for expulsion of a dead foetus (foetal death in utero): 600 mg of mifepristone in a single oral daily dose for 2 consecutive days. Mifegyne alone leads to expulsion in about 60%. Labour should be induced by the usual methods if it has not started within 72 hrs following the first administration of mifepristone.

Contraindications:

Mifegyne must not be administered if there is doubt as to the existence or age of the pregnancy or if an extra-uterine pregnancy is suspected. An ultrasound scan and/or measurement of Beta-hCG must be performed before administration. For first trimester abortions, Mifegyne is contraindicated if the pregnancy is beyond 49 days of amenorrhoea when used with misoprostol, or beyond 63 days of amenorrhoea when used with gemeprost.

Mifegyne should never be prescribed in the following situations: chronic adrenal failure, known allergy to mifepristone or to any component of the product, severe asthma uncontrolled by corticosteroid therapy, porphyrias. It must not be used if there are contraindications to the prostaglandins used in conjunction with Mifegyne.

As a precaution and in the absence of specific studies, Mifegyne should not be used in patients with renal failure, liver failure or malnutrition, or during breast feeding.

Warnings and precautions

General measures usually taken during pregnancy termination must be observed, including determination of blood group and rhesus factor.

Mifegyne is unlikely to have an effect on the ability to drive or use machines. During initial clinical trials, rare serious cardiovascular accidents similar to coronary spasm were reported following the administration of sulprostone, a prostaglandin analogue, no longer recommended. These events occurred in women >30 yrs of age who smoked >10 cigarettes a day.

No cases have been reported since the use of misoprostol or gemeprost The present experience is based upon 400,000 treatments (320,000 using misoprostol and 80,000 using gemeprost). However as a special precaution, the medical method is not recommended for use in women >35 yrs who smoke >10 cigarettes a day.

In case of suspected acute adrenal failure, dexamethasone administration is recommended. Due to the antiglucocorticoid acivity of mifepristone, the efficacy of long-term corticosteroid therapy may be decreased during the 3-4 days following Mifegyne intake. Therapy should be adjusted. In patients with asthma using inhaled corticosteroid therapy, it is recommended that the dose be doubled during the 48 hrs preceding administration of mifepristone and continue for about one week.

In patients with insulin dependent diabetes, the occurrence of gastro-intestinal disorders induced by the pregnancy or by the treatment, may alter insulin requirements.

Contraception: During clinical trials, pregnancies occurred between foetal expulsion and the resumption of menses. To avoid potential exposure of a subsequent pregnancy to mifepristone, it is recommended that conception be avoided during the next menstrual cycle using reliable contraception. Where a pregnancy occurs with an intra-uterine device in situ, the device must be removed before administration of mifepristone.

Teratogenicity: No effect was observed in rats and mice surviving foetal exposure. In rabbits however, isolated cases of severe abnormalities occurred (cranial vault, brain and spinal cord). The number of foetal anomalies was not statistically significant and no dose-effect was observed. In monkeys, the number of foetuses surviving the abortifacient action of mifepristone was insufficient for a conclusive assessment. Uncommon cases of malformations have occurred in the human foetus or infant but the exact role of mifepristone, prostaglandin analogue or coincidental event is unknown. Patients must be informed that in the event of failure and a continuing pregnancy the foetus may be exposed to a risk of malformation.

Failures: In clinical trials, the results vary according to the prostaglandin used and the time of administration. The success rate is up to 95.7% when misoprostol is used orally up to 49 days of amenorrhoea, and with gemeprost applied vaginally it reaches 98.7% up to 49 days of amenorrhoea and 94.8% up to 63 days of amenorrhoea. Failures occur in 1.3 to 7.5%, of which 0-1.5% are ongoing pregnancies, 1.3-4.6% are due to incomplete expulsion and 1.4% require haemostatic curettage.

Bleeding: Special care should be given to patients with haemorrhagic disorders, hypocoagulability or anaemia. The decision to use a medical or surgical method should be decided with relevant specialist consultation.

In the case of first trimester abortion the patient must be informed of the occurrence of prolonged vaginal bleeding (about 9 days after Mifegyne intake) which may be heavy. Bleeding occurs in almost all cases and is not proof of complete expulsion.

The patient should be informed not to travel far away from the prescribing centre until complete expulsion has been confirmed. She must receive precise instructions about who to contact and where to go, in the event of problems, particularly in the case of very heavy vaginal bleeding. A follow up visit must take place within a period of 10-14 days after administration of Mifegyne to verify that expulsion is complete. Persistence of vaginal bleeding at this point could indicate incomplete abortion, or an unnoticed extra-uterine pregnancy.

In the case of softening and dilatation of the cervix prior to surgical termination the woman must be informed of the risk of bleeding and of the rare occurrence (0.9%) of expulsion prior to surgical termination.

Adverse effects

Urogenital: It is very common for women to experience uterine contractions or cramping (10-45%) in the hours following prostaglandin intake. Bleeding increases with gestational age. Heavy bleeding occurs in about 5% of cases and from 0-1.4% may require haemostatic curettage. Uterine rupture has been uncommonly reported after prostaglandin intake for induction of second trimester termination or labour induction for foetal death, particularly in multiparous women or those with a caesarian scar.

Gastrointestinal: Nausea, vomiting and diarrhoea are very common after prostaglandin intake.

Cardiovascular: Uncommonly, hypotension (0.25%)

Hypersensitivity and skin: Uncommonly, skin rashes (0.2%). Single cases of urticaria, erythroderma, erythema nodosum and epidermal necrolysis have been reported.

Other systems: Vagal symptoms are common (hot flushes, diziness, chills). Fever is uncommon. Rare cases of headaches, malaise have been reported.

Interactions

A decrease of the efficacy of the prostaglandin can theoretically occur due to the antiprostaglandin properties of non-steroidal anti-inflammatory drugs.

Overdosage

Single doses of mifepristone up to 2G caused no unwanted reaction. In the event of massive ingestion, signs of adrenal failure might occur. Acute intoxication may require admission to hospital and if relevant treatment with dexamethasone.

Pharmaceutical precautions

No known incompatibilities.

Shelf life 3 yrs.

Further information

Mifegyne must only be used in accordance with the legislation governing termination of pregnancy. It must be prescribed by a doctor and administered by a health professional in a licensed premise. It will not be available through pharmacies.

Source: Istar Ltd, 8 Braithwaite St, Karori, Wellington. Phone: (04) 476 8112 Fax: (04) 476 6380

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