Letrovitae Special Precautions

Menopausal state: In patients whose menopausal status is unclear, luteinizing hormone (LH), follicle stimulating hormone (FSH) and/or estradiol level should be measured before initiating treatment with LETROVITAE. Only women of postmenopausal endocrine state should receive letrozole.
Bone effects: Letrozole is a potent estrogen-lowering agent. Women with a history of osteoporosis and/or fractures, or who are at increased risk of osteoporosis should have their bone mineral density formally assessed prior to the commencement of extended adjuvant and extended adjuvant treatment and monitored during and following treatment with letrozole. The treatment or prophylaxis of osteoporosis should be initiated as appropriate and carefully monitored. In adjuvant setting a sequential treatment schedule (letrozole 2 years followed by tamoxifen 3 years) could also be considered depending on the patient's safety profile (see Dosage & Administration, Adverse Reactions and PHARMACOLOGY: Pharmacodynamics under Actions).
Tendonitis and tendon rupture: Tendonitis and tendon ruptures (rare) may occur. Close monitoring of the patients and appropriate measures (e.g. immobilisation) must be initiated for the affected tendon (see Adverse Reactions).
Other warnings: Co-administration of letrozole with tamoxifen, other antiestrogens or estrogen-containing therapies should be avoided as these substances may diminish the pharmacological action of LETROVITAE (see Interactions).
Warnings on excipients: This medicine contains lactose. Patients with rare hereditary problems of galactose intolerance, Lapp lactase deficiency (failure observed in certain populations of Lapland) or glucose or galactose absorption problems should not take this medicine.
This medicine can cause allergic reactions because it contains tartrazine.
May cause asthma, especially in patients allergic to acetylsalicylic acid.
May cause allergic reactions such as angioedema, asthma, urticaria and anaphylactic shock.
Use in athletes: Patients should be warned that this medicine contains letrozole, which can produce a positive result in doping control tests.
Effects on ability to drive and use machines: Letrozole has minor influence on the ability to drive and use machines. Since fatigue and dizziness have been observed with the use of Letrozole and somnolence has been reported uncommonly, caution is advised when driving or using machines.
Renal impairment: Letrozole has not been investigated in a sufficient number of patients with creatinine clearance lower than 10 ml/min. The potential risk/benefit to such patients should be carefully considered before the administration of letrozole.
Hepatic impairment: In patients with severe hepatic impairment (Child-Pugh C), systemic exposure and terminal half-life were approximately doubled compared to healthy volunteers. Such patients should therefore be kept under close supervision (see PHARMACOLOGY: Pharmacokinetics under Actions).