General:
The use of GnRH agonists may cause reduction in bone mineral density.
In men, preliminary data suggest that the use of a bisphosphonate in combination with a GnRH agonist may reduce bone mineral loss.
Particular caution is necessary in patients with additional risk factors for osteoporosis (e.g. chronic alcohol abuse, smokers, long-term therapy with drugs that reduce bone mineral density, e.g. anticonvulsants or corticoids, family history of osteoporosis, malnutrition).
Rarely, treatment with GnRH agonists may reveal the presence of a previously unknown gonadotroph cell pituitary adenoma. These patients may present with a pituitary apoplexy characterised by sudden headache, vomiting, visual impairment and ophthalmoplegia.
There is an increased risk of incident depression (which may be severe) in patients undergoing treatment with GnRH agonists, such as triptorelin. Patients should be informed accordingly and treated as appropriate if symptoms occur.
Mood changes have been reported. Patients with known depression should be monitored closely during therapy.
Men:
Initially, triptorelin, like other GnRH agonists, causes a transient increase in serum testosterone levels. As a consequence, isolated cases of transient worsening of signs and symptoms of prostate cancer may occasionally develop during the first weeks of treatment. During the initial phase of treatment, consideration should be given to the additional administration of a suitable anti-androgen to counteract the initial rise in serum testosterone levels and the worsening of clinical symptoms.
A small number of patients may experience a temporary worsening of signs and symptoms of their prostate cancer (tumour flare) and temporary increase in cancer related pain (metastatic pain), which can be managed symptomatically.
As with other GnRH agonists, isolated cases of spinal cord compression or urethral obstruction have been observed. If spinal cord compression or renal impairment develops, standard treatment of these complications should be instituted, and in extreme cases an immediate orchiectomy (surgical castration) should be considered. Careful monitoring is indicated during the first weeks of treatment, particularly in patients suffering from vertebral metastasis, at the risk of spinal cord compression, and in patients with urinary tract obstruction.
After surgical castration, triptorelin does not induce any further decrease in serum testosterone levels.
Long-term androgen deprivation either by bilateral orchiectomy or administration of GnRH analogues is associated with increased risk of bone loss and may lead to osteoporosis and increased risk of bone fracture.
Androgen deprivation therapy may prolong the QT interval.
In patients with a history of or risk factors for QT prolongation and in patients receiving concomitant medicinal products that might prolong the QT interval (see section 4.5) physicians should assess the benefit risk ratio including the potential for Torsade de pointes prior to initiating GONAPEPTYL,
In addition, from epidemiological data, it has been observed that patients may experience metabolic changes (e.g. glucose intolerance, fatty liver), or an increased risk of cardiovascular disease during androgen deprivation therapy. However, prospective data did not confirm the link between treatment with GnRH analogues and an increase in cardiovascular mortality. Patients at high risk for metabolic or cardiovascular diseases should be carefully assessed before commencing treatment and adequately monitored during androgen deprivation therapy.
Administration of triptorelin in therapeutic doses result in suppression of the pituitary gonadal system. Normal function is usually restored after treatment is discontinued. Diagnostic tests of pituitary gonadal function conducted during treatment and after discontinuation of therapy with GnRH analogues may therefore be misleading.
Women:
Gonapeptyl Depot should only be prescribed after careful diagnosis (e.g. laparoscopy).
It should be confirmed that the patient is not pregnant before prescription of triptorelin.
Since menses should stop during GONAPEPTYL Depot treatment, the patient should be instructed to notify her physician if regular menstruation persists.
Loss of bone mineral density
The use of GnRH agonists is likely to cause reduction in bone mineral density averaging 1% per month during a six month treatment period. Every 10% reduction in bone mineral density is linked with about a two to three times increased fracture risk. For this reason, therapy without add back treatment should not exceed a duration of 6 months. After withdrawal of treatment, the bone loss is generally reversible within 6 - 9 months.
In the majority of women, currently available data suggest that recovery of bone loss occurs after cessation of therapy.
No specific data is available for patients with established osteoporosis or with risk factors for osteoporosis (e.g. chronic alcohol abuses, smokers, long-term therapy with drugs that reduce bone mineral density, e.g. anticonvulsants or corticoids, family history of osteoporosis, malnutrition, e.g. anorexia nervosa). Since reduction in bone mineral density is likely to be more detrimental in these patients, treatment with triptorelin should be considered on an individual basis and only be initiated if the benefits of treatment outweigh the risk following a very careful appraisal. Consideration should be given to additional measures in order to counteract loss of bone mineral density.
Uterine myomas and endometriosis:
A supervening metrorrhagia in the course of treatment is abnormal (apart from the first month) and should lead to verification of plasma oestrogen level. Should this level be less than 50 pg/ml, possible associated organic lesions should be sought. After withdrawal of treatment, ovarian function resumes, e.g. menstrual bleeding will resume after 7-12 weeks after the final injection.
Non-hormonal contraception should be used during the initial month of treatment as ovulation may be triggered by the initial release of gonadotropins. It should also be used from 4 weeks after the last injection until resumption of menstruation or until another contraceptive method has been established.
During treatment of uterine myomas the size of uterus and myoma should be determined regularly, e.g. by means of ultrasonography. Disproportionally fast reduction of uterus size in comparison with the reduction of myoma tissue has in isolated cases led to bleeding and sepsis.
There have been a few reports of bleeding in patients with submucous fibroids following GnRH analogue therapy. Typically the bleeding has occurred 6 - 10 weeks after the initiation of therapy.
Children:
The chronological age at the beginning of therapy should be under 9 years in girls and under 10 years in boys.
In girls' initial ovarian stimulation at treatment initiation, followed by the treatment-induced oestrogen withdrawal, may lead, in the first month, to vaginal bleeding of mild or moderate intensity.
After finalising the therapy, development of puberty characteristics will occur. Information with regards to future fertility is still limited. In most girls' menses will start on average one year after ending the therapy, which in most cases is regular.
Bone mineral density may decrease during GnRH therapy for central precocious puberty. However, after cessation of treatment subsequent bone mass accrual is preserved and peak bone mass in late adolescence does not seem to be affected by treatment.
Slipped capital femoral epiphysis can be seen after withdrawal of GnRH treatment. The suggested theory is that the low concentrations of oestrogen during treatment with GnRH agonists weakens the epiphyseal plate. The increase in growth velocity after stopping the treatment subsequently results in a reduction of the shearing force needed for displacement of the epiphysis.
The treatment of children with progressive brain tumours should follow a careful individual appraisal of the risks and benefits.
Pseudo-precocious puberty (gonadal or adrenal tumour or hyperplasia) and gonadotropin-independent precocious puberty (testicular toxicosis, familial Leydig cell hyperplasia) should be precluded.
Allergic and anaphylactic reactions have been reported in adults and children. These include both local site reactions and systemic symptoms. The pathogenesis could not be elucidated. A higher reporting rate was seen in children.
Idiopathic intracranial hypertension
Idiopathic intracranial hypertension (pseudotumor cerebri) has been reported in paediatric patients receiving triptorelin. Patients should be warned for signs and symptoms of idiopathic intracranial hypertension, including severe or recurrent headache, vision disturbances and tinnitus. If idiopathic intracranial hypertension occurs, discontinuation of triptorelin should be considered.