<p>There is a general opinion, based on statistical evidence that users of combined oral contraceptives experience, more often than non-users, venous thromboembolism, arterial thrombosis, including cerebral and myocardial infarction and subarachnoid haemorrhage. Full recovery from such disorders does not always occur, and it should be realized that in a few cases they are fatal. Although Norethisterone does not contain oestrogen, one should keep the possibility of an increased thromboembolic risk in mind, particularly where there is a history of thromboembolic disease or in the presence of severe diabetes with vascular changes or sickle-cell anaemia.<br />
<br />
In rare cases benign, and in even rarer cases, malignant liver tumours leading in isolated cases to life-threatening intra-abdominal haemorrhage have been observed after the use of hormonal substances such as the one contained in Norethisterone. If severe upper abdominal complaints, liver enlargement or signs of intra-abdominal haemorrhage occur, a liver tumour should be included in the differential diagnosis and, if necessary, the preparation should be withdrawn.<br />
Norethisterone can influence carbohydrate metabolism. Parameters of carbohydrate metabolism should be examined carefully in all diabetics before and regularly during treatment.<br />
<br />
Reasons for stopping Norethisterone immediately-</p>

<ul>
	<li>Occurrence for the first time of migrainous headaches or more frequent occurrence of unusually severe headaches</li>
	<li>Sudden perceptual disorders (e.g. disturbances of vision or hearing)</li>
	<li>First signs of thrombophlebitis or thromboembolic symptoms, feeling of pain and tightness in the chest</li>
	<li>Pending operations (six weeks beforehand), immobilisation (e.g. after accidents)</li>
	<li>Onset of jaundice, hepatitis, general pruritus</li>
	<li>Significant rise in blood pressure</li>
	<li>Pregnancy.</li>
</ul>