 |
|
||||
|
|||||
| About | Latest Articles | Back-Issues | Articles
|
Search | Instructions | Online Submission | Subscribe | Etcetera | Contact |
| |||||||||||||||||||||
|
Pregnancy, epilepsy and pharmacotherapy.
We now possess a variety of specific anticonvulsant drugs which may produce adverse effects in pregnancy. The effects of epilepsy on pregnancy and that of pregnancy on epilepsy are subtle and complex. The interactions between anticonvulsant drug therapy, pregnancy and the growing fetus and their implications on the control of epilepsy need evaluation for accurate clinical diagnosis and management. Whilst managing epilepsy in pregnancy, the obstetrician feels insecure due to an incomplete understanding of epilepsy. In turn, the neurosurgeon and the neurologist feel handicapped by their limited appreciation of the finer aspects of pregnancy. Dowling's (1977)[10] statement: "it is difficult to interest doctors and medical students in epilepsy" must be understood in the context of that by Lance (1977)[39] "a doctor's negative attitude may deleteriously affect the perspective of the epileptic patients." If expert medical management is to be made available for the control of seizures in pregnant women and for the safety of the fetus, neuroscientists and obstetricians need to work together so that epilepsy no longer possess a great problem in the majority of the patients. We can thus help women with epilepsy to lead normal life including marriage, child bearing and employment.[18]"Evils do not disappear because people disapprove of them unless conditions at their roots are changed" (Friedenberg, 1965).[17] The aim of this presentation is to help bring about such changes by providing basic information regarding interactions between epilepsy, pregnancy, fetus and antiepileptic drugs. EPILEPTIC DISORDERS DURING PREGNANCY I. Definition Epilepsy is a symptom characterized by a paroxysmal and transitory disturbance of cerebral functions, which develop suddenly, cease spontaneously and exhibit a conspicuous tendency to recurrence.[72] Commonly the attacks of epilepsy are known as seizures or fits. Between 0.3 and 0.6% of pregnant women have epilepsy.[5] II. Classification The various seizure disorders may be classified as follows:[8] 1. Generalized seizures (a) Convulsive. (i) Tonic-clonic major motor without focal onset (grand mal). (ii) Clonic (myoclonic) generalized. (b) Non-convulsive. (i) Brief typical absence (Petit mal). (ii) Brief atypical absence. 2. Focal seizures (a) Simple. (i) Motor (Brief focal only). (ii) Sensory (Focal with Jacksonian march), (iii) Autonomic (Multifocal). (iv) Focal continuous-epilepsia partialis continua. (b) Complex. (i) Psychomotor predominating. (ii) Psychosensory predominating. 3. Pseudoseizures (Hysterical seizures) 4. Conditions with some features of epilepsy Narcolepsy, fainting, nightmares, rage attacks (dyscontrol), transient ischaemic attack, migraine and Stokes-Adam syndrome. EFFECTS OF PREGNANCY ON THE SEIZURES It is not uncommon for some epileptic women to be free from attacks during pregnancy. Others may worsen when pregnant. The truth probably is that epilepsy may be influenced for better or worse by many different factors.[72] I. Maternal factors Hormonal and metabolic factors, respiratory changes, psychological problems, non-compliance and the altered disposition of antiepileptic drugs may modify the seizure frequency. The onset of epilepsy during pregnancy may be due to coincidence.[63] Several other factors may be related to the exacerbation of epilepsy during pregnancy e.g. maternal age at delivery, number of previous deliveries, duration of epilepsy prior to pregnancy and its therapy.[30] II. Epileptogenecity of pregnancy There are some women whose first seizure occurs in pregnancy but there is no study which provides statistical evidence that pregnancy is likely to start the common varieties of epilepsy.[27] Non eclamptic, non-febrile, 'gestational epilepsy' occurs for the first time in pregnancy, remits in the puerperium and then returns only in subsequent pregnancies.[27] Knight and Rhind[37] found only two such patients amongst their 59, epileptic mothers studied through 153 pregnancies. Furthermore, it is rare in a case of preexisting epilepsy for seizures to recur during pregnancy after a prolonged seizure-free period. The apparent rarity of these phenomena suggests that pregnancy per se is not a potent epileptogenic agent.[27] III. Type of epilepsy Women with partial complex (temporal lobe) seizures or generalized epilepsy with focal characteristics are worse off during pregnancy whereas those with the classic Petit mal epilepsy are better off. Bardy5 noted the highest incidence of grand mal seizures during last trimester of pregnancy while most psychomotor seizures were noted during puerperium. Status epilepticus,[20] which is not more frequent during pregnancy, presents as a life threatening emergency for both mother and child.[63] Amongst major catagories, constitutional (idiopathic), generalized, tonic-clonic seizures are the most common presentation of chronic seizure disorders, noted during pregnancy while the non-convulsive, generalized seizures (Petitmal) are rarely seen in this age group. Consistently repeated, acute, focal or generalized tonic-clonic seizures with focal onset, may be an expression of an underlying focal or generalized cerebral pathological lesions. II. Course of epilepsy There is no reliable data which allows prediction of an individual's course of epilepsy during pregnancy[63] except the pregestational fit frequency.[9],[37] A history of catamenial seizures seems not to be a risk factor.[9] Women, seizure-free for the previous 2 years usually remain seizure-free during pregnancy. Women, who remain seizure-free for 9 months preceding pregnancy are at 20-40% risk of exacerbation of seizures during pregnancy. And those who convulse at least once monthly before hand usually worsen during pregnancy. Women, who had very frequent seizures (more frequently in a month) were four times more likely to have an increased frequency of seizures during pregnancy than those with occasional seizures (less than one in three months). In Knight and Rhind's study[37] of 153 pregnancies in 59 epileptics, the seizure frequency was increased in 45%, unchanged in 50% and decreased in 5%. Similar results were also obtained by others[17],[60] while a few[4],[54] have reported unchanged frequency during pregnancy and puerperium. Mothers carrying male fetus were twice as likely to deteriorate than those carrying a female fetus.[37] ASSESSMENT AND THERAPEUTIC CONSIDERATIONS When the patient is a known epileptic (idiopathic) and is on antiepileptic drug therapy, the problem, primarily, revolves around the maintenance of serum concentration of drug in the therapeutic range. The range during the non-pregnant state might be inappropriate during pregnancy because of changes in the relation between the drug concentration and its effect. There is altered antiepileptic drug disposition during pregnancy when the daily dose is kept constant. If the seizures occur for the first time during the later half of pregnancy the first suspicion should be of eclampsia particularly if there is associated hypertension, proteinuria and edema.[69] In the absence of these features, if acute, generalized or focal seizures suddenly develop in a non-epileptic pregnant woman, then non-obstetric diagnostic possibilities must be considered and such patients should be investigated and treated in the same manner as those developing epilepsy unassociated with pregnancy. A particularly likely cause during pregnancy is expansion of an arterio-venous malformation or a brain tumor. During puerperium, a siezure may be the first evidence of cortical venous thrombosis.[27] Non-obstetric causes of epilepsy, in this age group include brain tumours (pituitary adenoma, meningioma, glioma, neurofibroma etc.); cerebrovascular lesions i.e. occlusive (cortical venous thrombosis, dural sinus thrombosis) and haemorrhagic (aneurysms, arterio-venous malformations); head injuries; drug intoxication or withdrawal (sedative, alcohol); infections (meningitis, infective granulomas, encephalitis); metabolic (uremia, hepatic failure, hypo- and hypernatremia, alkalosis, hyperventilation, acute porphyriaetec) and endoernola disorders (hypo- or hyperglycemia, hypo- and hyperglycemia, diabetic ketoacidosis, pituitary apoplexy). These should be excluded before labelling non-febrile seizures as idiopathic. In a patient in whom seizures develop for the first time during pregnancy, a detailed neurological history and examination is mandatory. A history of preexisting medical illness, drug intake, head injury, infection or a tumor may provide a working clue to the correct diagnosis. Complete hematological (including metabolic) studies, skull X-rays and electroencephalography should be done. Lumbar puncture is contraindicated only in the presence of signs of increased intracranial pressure (headache, vomiting and papilloedema). CT scan of brain is strongly recommended, the amount of radiation produced by this procedure being approximately that of the usual series of plain skull X-rays.[8] The constrast material employed in CT scans and in cerebral angiography is physiologically inert with respect to iodine and does not produce fetal thyroid abnormalities.[8] Therefore, pregnancy is not a contraindication for neuroradiological diagnostic studies. However, concern for safety of the mother and her fetus compels us to consider carefully any investigation that requires radiation exposure. Treatment of the patient with a seizure disorder is directed at eliminating the cause of the seizures and suppressing the expression of the seizures to overcome their deleterious effects on mother and fetus, and in cases of uncontrolled seizures therapeutic abortion is sometimes indicated.[35] PHARMACOTHERAPY OF SEIZURES IN PREGNANCY I. Aim During pregnancy and in the puerperium a fine balance should be maintained. No harm should occur to the baby because of the drug. At the same time no harm must come to the mother or baby because mother is being inadequately treated.[63] It has been suggested that a regimen should be established to provide optimal seizure control with the fewest side effects using the least possible number of drugs.[47] II. Objective In case of a single seizure some experts prefer to with old treatment.8 In case of repetative seizures, there is no such doubt-the fits must be controlled by drugs. Whenever possible, it is preferable to treat patients adequately with one anticonvulsant drug, making sure that its blood levels are in the therapeutic range. This is important as in the pregnant epileptic plasma drug concentration declines if oral dose is kept constant.[8] Monotherapy is preferred to polytherapy as the latter increases the incidence of congenital malformations in the fetus. III. Therapy There is no unanimity regarding the drug of choice. Various workers, according to their experiences, choose one of the following three drugs for major chronic convulsive seizures during pregnancy(i) diphenylhydantoin[8] (ii) phenobarbitone[44] (iii) carbamazepine. Diphenylhydantoin is given in the oral dose of 300-600 mg per day to achieve therapeutic range of 10-25 ug/ml of serum which is attained in approximately 2 weeks.[9] If seizures are not controlled despite high doses of this drug then another antiepileptic drug is either added to it or substituted for it. Phenobarbitone is given in the oral dose of 90-120 mg daily in divided doses. The therapeutic level of phenobarbitone for seizure control is in range of 15-30 ug/ml of serum. Both these drugs are effective against variety of seizure disorders except Petit mal fits. When good control of seizure is not yet achieved with diphenylhydantoin and phenobarbitone, alone or in combination, then carbamazepine may be substituted in the divided doses of 600 mg daily and periodic monitoring of bone marrow function is done to look for the bone marrow depression which is a rare consequence. Petit mal seizure is rarely seen during pregnancy. Ethosuximide 250-500 mg three to four times daily, is the drug of choice. Caution has to be exercised as this drug is nephrotoxic and is toxic to the bone marrow. Diazepam may also be helpful in the dose of 5 to 10 mg three to four times daily. Troxidone is specifically contraindicated in pregnancy due to fetal trimethadione syndrome.[16] Valproic acid is a broad spectrum anticonvulsant drug but has significant teratogenic effect on fetus and is also hepatotoxic for mothers and thus should be avoided during pregnancy. After appropriate counselling, those women who do inadvertently take valproate in the first few months of pregnancy, should be subjected to amniocentesis for alpha-fetoprotein estimation[27] in order to detect dysraphic states. In the management of status epilepticus during pregnancy, oxygenation must be assured and blood must be examined for baseline levels of antiepileptic drugs, blood gases, electrolytes and glucose. Diazepam 10 mg is given intravenously over a period of two minutes and is repeated at 20 minute intervals for 2-3 times if necessary. In pregnant women, close to delivery diazepam crosses the placenta in significant amount and can cause generalized hypotonia and respiratory depression in neonates. Facilities for managing neonatal respiratory depression must be readily available. The maternal circulation must be maintained and cardiac rhythm should be monitored. Glucose is administered and dexamethasone (8 mg) is given intravenously to lower intracranial pressure. Diphenylhydantoin in the dose of 200-500 mg is given intravenously at a rate not faster than 50 mg per minute. Total dose should not exceed 1 gm. It is useful to monitor such patient electro-encephalographically since EEG seizure patterns may recur before appearance of subsequent seizures. If seizure pattern still continues, amobarbitol sodium in a dose of 120 to 250 mg (maximum upto 500 mg) can be given intravenously at a rate not to exceed 30 mg per minute. Should seizure still persist then the use of paraldehyde or general anaesthesia is made. There is no evidence that intravenous use of antiepileptic drugs which might be employed in the treatment of status epilepticus affect the fetus adversely. The injurious effects of continuous convulsions on the fetus are, on the other hand, only too well known. Status epilepticus in the pregnant woman is often related to subtherapeutic plasma levels of antiepileptic drugs because of non-compliance by the patient or inadequate maintenance of dose levels. If blood levels of the anti-epileptic drugs are maintained at levels found to be therapeutic before pregnancy, only 10-15% of epileptic women will convulse more frequently during pregnancy.[9] The control of seizures is better guided by the frequent estimates of serum antiepileptic drug levels during pregnancy. Improvement in seizure frequency follows attainment of adequate antiepileptic drug levels in serum or replacement of one drug by another that is more effective. The risk of recurrent seizures especially of status epilepticus-which result in maternal and fetal anoxia necessitates intensive antiepileptic therapy despite the theoretical risk of drug induced congenital anomalies. CONSEQUENCES OF PSYCHO-PHYSIOLOGICAL CHANGES I. On Antiepileptic Drug Pharmacokinetics The natural history of epilepsy,[8] in pregnant epileptic women interdigitates with antiepileptic drug metabolism and psycho-physiological changes occurring during pregnancy i.e. compliance, sleep deprivation, metabolic and hormonal changes, weight gain, mild chronic respiratory alkalosis and psychological changes. (a) Compliance Good compliance and adequate levels of antiepileptic drugs are not easily attained.[30] First of all, the pregnant epileptic woman is now increasingly aware of teratogenic effects of antiepileptic drugs. Either she or another physician may reduce or stop antiepileptic drug in an attempt at reducing the possibility of bearing an abnormal baby or that of harmful effects of these drugs on newborns and on breast feeding. Carelessness in drug taking is also an important factor. Poor compliance is not uncommon amongst epileptic mothers.[65] (b) Altered disposition of the drugs The physiological changes of pregnancy can lead to clinically important reductions in the blood concentrations of antiepileptic drugs in many ways.[29],[40],[45],[48],[54],[61] (i) Blood volume and weight gain: The total body water increases by as much as 8 litres during pregnancy.[57] Added to this, the volume of fetus and placenta increases the volume of distribution of the antiepileptic drugs given orally and therefore tend to lower the serum levels of these drugs if oral dose is kept unchanged. (ii) Serum proteins: Serum proteins relevent to drug binding undergo considerable changes in concentration.[66] Albumin (which binds acidic drugs such as diphenylhydantoin) decreases in concentration by up to 10 gm/litre.[59] In the presence of such reduced binding, any previous relation between serum diphenylhydantoin concentration and therapeutic effect will no longer hold since a greater proportion of the total drug concentration will be pharmacologically active. In such circumstances the clinical value of measuring diphenylhydantoin levels in serum is greatly reduced unless serum binding capacity is measured or is correlated with the fall in serum albumin.[62] (iii) Intestinal absorption:[58] The absorption of the oral antiepileptic drugs from the bowel may be significantly reduced. (iv) Liver metabolism:[48] Liver metabolism increases during pregnancy. Therefore, the maternal liver with an increased capacity for hydroxylation for some antiepileptic drugs e.g. diphenylhydantoin, results in lower plasma level of these drugs during pregnancy if the dose of such drugs is kept constant. Diphenylhydantoin is cleared at twice the rate found in the non-pregnant women.[41] (v) Renal clearance: Renal plasma flow has almost doubled by the last trimester of pregnancy.[11] Drugs which are eliminated unchanged by the kidneys are usually eliminated more rapidly but so far this has been shown to be clinically important in only a few cases.[61] The renal clearance may increase for diphenylhydantoin and phenobarbitone during the pregnancy, however the plasma protein binding of phenobarbitone remains unchanged. (vi) Interaction with other drugs ingested during pregnancy, e.g. benzodiazepines, lowers the concentration of diphenylhydantoin. (vii) Vitamin changes: The pregnant epileptic woman on antiepileptic therapy shows significantly lower serum folic acid levels than the normal pregnant woman. Folic acid, often given during pregnancy, is known to cause a reduction in the serum concentration of diphenylhydantoin and may itself have an epileptogenic effect.[65] In one study there was an inverse correlation between serum folate and diphenylhydantoin or phenobarbitone levels. The number of epileptic seizures during pregnancy showed no relation to serum folate levels.[24] According to this report, a low dose of 100 or 1000 ug of folate is a sufficient supplement for pregnant women on these drugs. (viii) Therapeutic range: It is not clear whether pregnancy alters the effects of drugs. It is possible that established therapeutic ranges might be inappropriate during pregnancy because of changes in the relationship between concentration and effect of these drugs but this factor is difficult to study.[61] (c) Precaution To avoid consequences of altered disposition of antiepileptic drugs during pregnancy, blood levels of these drugs should be measured each month and more frequently if seizures recur. The daily dose of diphenylhydantoin may triple especially in the second half of pregnancy. II. On The Seizure Susceptibility (a) Metabolic changes Mild compensatory alkalosis due to hyperventilation and lower concentrations of sodium, potassium, calcium and magnesium during pregnancy may precipitate seizures. (b) Hormonal changes In pregnancy, chorionic gonadotrophin reaches its peak in the first trimester and decreases towards the end of the pregnancy, while progesterone and oestradiol levels in blood and urine increase to reach maximum values during last trimester of pregnancy. Since the cerebral cortex is more sensitive to stimuli in pregnancy due to hormone-mediated intracellular electrolyte changes, the alteration in concentrations of these hormones should play some role in increasing susceptibility to seizures.[30] Activation of focal spikes and precipitation of epileptic seizures were reported in epileptic patients following intravenous injection of estrogen.[43] Canger et al[6] have found that patients with increased seizure frequency tended to have slightly higher estrogen levels than other pregnant epileptics. On the other hand, progesterone and testosterone have produced mild reduction of seizure susceptibility in rats, cats and dogs.[42],[49] Backstrom,[2],[3] has reported a positive correlation between the number of secondary generalized seizures and the mean estrogen/progesterone ratios, as well as a negative correlation to plasma progesterone levels in non-pregnant women with partial epilepsy. Therefore, the estrogen/progesterone ratio seems to be more relevant to susceptibility to seizures than the level of estrogen alone.[30] In the second and third trimesters, the cortisone level was higher in patients who had seizures during pregnancy than those without seizures.[56]; It has been suggested that glucocorticoid has epileptogenic effect not only in experimental animals but also in humans.[14],[64],[71] There was no significant correlation between the changes in concentrations of human growth hormone, TSH, T3, T4 and frequency of seizures.[36] (c) Psychological mechanisms Anxiety, sleep deprivation and poor compliance contribute to precipitation of seizures. CONSEQUENCES OF SEIZURES AND THEIR THERAPY Today, the majority of epileptic women can safely conceive and give birth in the same way as non-epileptic women. However, since risks and difficulties during pregnancy, delivery and child care remain greater for epileptics than for non-epileptics, some special considerations are necessary.[30] I. On Pregnancy, Labour and Puerperium Present data indicates that there is a slightly increased risk of bleeding throughout pregnancy[70] and a higher incidence of ablato placentae in epileptic women.[46],[70] The incidence of spontaneous abortion is higher in epileptic mothers using anti-epileptic drugs than in normal pregnant women, while there was no significant difference in the incidence of artificial abortion.[52] The increase in the incidence of spontaneous abortion is at least partly explained by a decrease in thyroid hormonal concentrations as a result of antiepileptic medications during pregnancy,[33] since thyroid hormones play a significant role in maintaining pregnancy.[39] However, Koch et al[38] have reported that incidence of threatened abortion does not seem higher in epileptic women than in the general population. Induction of labour and intervention during delivery are significantly more frequent in epileptic women[52] than in controls.[13] In the gravid epileptic patients, the duration of labour is slightly shorter and status epilepticus, pre-eclampsia, abruptio placentae, polyhydramnios, assisted delivery, caesarean section, prematurity and intrauterine growth retardation have all been reported to be higher.[25] Bleeding appears to be the only significantly increased complication during pregnancy, labour and delivery in epileptic women,[45] due to hypotonic uterine activity, antiepileptic drugs and placental complications. In puerperium, plasma clearance of antiepileptic drugs decreases to pregestational rates within 6 weeks with most of the changes taking place in the first few weeks. The plasma levels of diphenylhydantoin and phenobarbitone increase approaching the levels before pregnancy[9] Therefore, blood levels of these drugs should be monitored each week post partum.[51] If the daily dose of an antiepileptic drug has been increased during pregnancy then appropriate adjustments should be made after delivery in order to avoid intoxication. II. On Fetus and Newborn (a) Passage of drugs to fetus Placenta is essentially a lipid barrier between the maternal and fetal circulations. Drugs cross the placenta by passive diffusion. A lipid soluble un-ionised drug of low molecular weight will cross the placenta more rapidly than a more polar drug.[61] For most antiepileptic drugs, the ratio of concentration in the umbilical cord blood and that in the maternal venous blood is one,[53] while with valproic acid and diazepam it is significantly higher.[68] (b) Deleterious effects of the drugs and seizures (i) On fetus: Malformations, morbidity, mortality. No drug is totally safe for the fetus but polytherapy carries more risk than monotherapy. Higher rates of retardation in utero,[5],[30] (due to lower thyroxine and thyrotropine levels); fetal distress[50] (due to hypoxia in mother in the subpartum period); neonatal mortality[23] (1.2 to 2.5 fold); congenital malformations,[1],[15] (2 to 2.5 fold); hemorrhagic tendencies in fetus and neonates (due to decrease in vitamine-K dependent clotting factors),[9] and physical and mental subnormality in infants[22] are all well documented as a result of seizures and their therapy in pregnant women. While the majority of epileptic pregnant mothers taking antiepileptic drugs give birth to healthy babies, 14% of live births from these women have congenital defects compared to 5.6% of control.[15],[67] The incidence of major malformations is 5-10%,[28] and for minor malformations the rate is more than double.[31] Commonest malformations are congenital heart diseases, cleft lip and cleft palate. Renal, genital, skeletal and C.N.S. malformations are less common. Fetal hydantoin syndromm[21] and fetal trimehtadione syndrome[16],[19] are well known entities. The fetal hydantoin syndrome is characterized by craniofacial anomalies (variation in size and shape of head with widening of fontanelle and prominent ridges of cranial sutures, hyperteleorism, saddled, broad nasal bridge and short upturned nose, epicanthal folds, ptosis and strabismus, prominent low-set malformed ears; and wide mouth with prominent lips), psycosomatic retardation (mental dullness and short stature) and limb defects (hypoplasia of the distal phalanges and nails, finger-like thumbs, and variations in palmer creases hand markings). In trimethadione syndrome, affected infants show developmental delay, speech disturbances, low set ears, V-shaped eyebrows, palatal anomalies and irregular teeth. Carbamazepine is known to cause significant bone marrow depression. In causing these congenital anomalies, antiepileptic drugs may interact with genetic factors and may interfere with cellular proliferation at palatal shelves. Valproate has been incriminated in the causation of hydrocephalus and spina bifida and therefore it has been suggested that women exposed to valproic acid in the first trimester should be offered amniocentesis.[12],[67] (ii) On infants: Barbiturate withdrawl They may show transient symptoms of antiepileptic withdrawal,[26],[30] i.e. hyperirritability, tremors, convulsions, vomiting, poor suckling, excessive crying, and rarely hyperactivity and sleep disturbances. If seizures occur, small doses of phenobarbitone (3-5 mg/kg/day) may be necessary. (iii) On child: Risk of seizures The risk of an epileptic adult having child with epilepsy is only about one in 30.[27] Janz et al[29] reported on a retrospective study of 768 children of 414 families in which one parent had epilepsy and the other neither epilepsy nor febrile convulsions. Epilepsy occurred in 3.4% of all children-a risk about five times that of the general population. The risks were higher when the parent had epilepsy of unknown origin, when it was the mother rather than the father who was epileptic, and when the children themselves had already shown febrile convulsions. If a child of an epileptic parent does have febrile convulsions then the child's chances of having epilepsy are increased.[27] III On Breast Feeding The supply of mother's milk is important to the infant as it provides immunological protection[30] Virtually all drugs pass into the breast milk. Previous dilution of drug in the mother's body, however, when coupled with the small amount of milk consumed by the infant usually mean that the amount of drug pass to the baby is clinically unimportant.6l There are two main categories of antiepileptic drugs so far as breast feeding is concerned. (i) Drugs which reach the baby in an insignificant dose are diphenylhydrantoin and sodium valproate. Therefore breast feeding should not be stopped when epileptic mother is receiving these drugs. (ii) Drugs which reach the baby in sufficient dose to be harmful are barbiturates, benzodiazepine, primidone etc. Mothers taking these drugs should reduce or discontinue breast feeding for the first 7 days postpartum.[32] Slow phenobarbitone and diazepam metabolism may present some hazards to the infant besides respiratory depression. If the mother desires to breast feed the anticonvulsant regimen should be modified before or during pregnancy. CONCLUSION: MEDICAL PRACTICE: ADVICE The epileptic mother should be kept informed on the nature of her illness and its outlook, the therapeutic requirement and attendant risks of treatment. The doctors have to balance two conflicting interests in treating the epileptic pregnant woman. Keeping the risks of seizures in mind especially that of status epilepticus, the patient should be advised to continue antiepileptic drug therapy in effective therapeutic dosages, as judged by periodic estimation of their serum levels and clinical effects, but with the patient's acceptance of the risks of congenital malformations in baby. It should be emphasised that the teratogenic hazards of antiepileptic drug therapy is slight (14% as compared to 5.6% in controls) and that the risk to the child from the maternal seizures with attendant hypoxia and acidosis is much greater.[67] Therefore more harm than good may result if a woman has an increased number of major seizures due to reduction of arrest of the anticonvulsant drug therapy.[27]
I gratefully thank Prof. S. K. Pandya, Head, Department of Neurosurgery, K.E.M. Hospital, Bombay for his persistent encouragement, guidance and invaluable suggestions during preparation of this article. I am truly thankful to Mr. V. B. Ambetkar for his secretarial assistance.
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|||||||
