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Femara

Last reviewed on RxList: 12/14/2018
Femara Side Effects Center

Last reviewed on RxList 12/14/2018

Femara (letrozole) is a non-steroidal aromatase inhibitor (lowers estrogen production) used to treat breast cancer in postmenopausal women. Femara is often given to women who have been taking tamoxifen (Nolvadex, Soltamox) for 5 years. Femara is available in generic form. Common side effects of Femara include:

  • hot flashes,
  • warmth in your face or chest,
  • hair loss,
  • joint/bone/muscle pain,
  • tiredness,
  • unusual sweating or night sweats,
  • nausea,
  • diarrhea,
  • dizziness,
  • trouble sleeping,
  • drowsiness,
  • weight gain,
  • weakness,
  • flushing (warmth, redness, or tingly feeling),
  • headache,
  • constipation,
  • numbness/tingling/weakness/stiffness in your hand or fingers, or
  • pain in your hand that spreads to your arm, wrist, forearm, or shoulder.

The recommended dose of Femara is one 2.5 mg tablet administered once a day, without regard to meals. Other drugs may interact with Femara. Tell your doctor all prescription and over-the-counter medications and supplements you use. Femara must not be used during pregnancy. It may harm a fetus. Femara is used mainly in women after menopause. If you have recently gone through menopause, discuss birth control with your doctor. Do not use birth control containing estrogen. It is unknown if this drug passes into breast milk and may harm a nursing infant. Breastfeeding while using this drug is not recommended.

Our Femara (letrozole) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Femara Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Common side effects may include:

  • dizziness, drowsiness, weakness, tired feeling;
  • hot flashes, warmth in your face or chest;
  • bone pain, muscle or joint pain;
  • flushing (warmth, redness, or tingly feeling);
  • headache;
  • increased sweating; or
  • swelling, weight gain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Femara (Letrozole)

Femara Professional Information

SIDE EFFECTS

The following adverse reactions are discussed in greater detail in other sections of the labeling.

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reactions rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Adjuvant Treatment Of Early Breast Cancer

In study, BIG 1-98, the median treatment duration of adjuvant treatment was 60 months and the median duration of follow-up for safety was 96 months for patients receiving Femara and tamoxifen.

Certain adverse reactions were prospectively specified for analysis (see Table 1), based on the known pharmacologic properties and side effect profiles of the two drugs.

Adverse reactions were analyzed irrespective of whether a symptom was present or absent at baseline. Most adverse reactions reported (approximately 75% of patients who reported AEs) were Grade 1 or Grade 2 applying the Common Toxicity Criteria (CTC) Version 2.0/Common Terminology Criteria for Adverse Events (CTCAE), Version 3.0. Table 1 describes adverse reactions (Grades 1-4 and Grades 3-4) irrespective of relationship to study treatment in the adjuvant trial for the monotherapy arms analysis (safety population).

Table 1: Patients with Adverse Reactions (CTC Grades 1-4,) in the Adjuvant Study – Monotherapy Arms Analysis (Median Follow-up 96 Months; Median Treatment 60 Months)

Adverse Reactions Grades 1-4 Grades 3-4
Femara
N = 2448
n (%)
Tamoxifen
N = 2447
n (%)
Femara
N = 2448
n (%)
Tamoxifen
N = 2447
n (%)
Patients with any adverse reaction 2309 (94.3) 2212 (90.4) 636 (26.0) 606 (24.8)
Hypercholesterolemia* 1280 (52.3) 700 (28.6) 11 (0.4) 6 (0.2)
Hot flashes* 819 (33.5) 929 (38.0) - - - -
Arthralgia/arthritis* 621 (25.4) 504 (20.6) 84 (3.4) 50 (2.0)
Bone fractures1 361 (14.7) 280 (11.4) - - - -
Night sweats* 356 (14.5) 426 (17.4) - - - -
Weight increase* 317 (12.9) 378 (15.4) 27 (1.1) 39 (1.6)
Nausea* 284 (11.6) 277 (11.3) 6 (0.2) 9 (0.4)
Bone fractures**2 249 (10.2) 175 (7.2) - - - -
Fatigue (lethargy, malaise, asthenia)* 235 (9.6) 250 (10.2) 6 (0.2) 7 (0.3)
Myalgia* 221 (9.0) 212 (8.7) 18 (0.7) 14 (0.6)
Vaginal bleeding* 129 (5.3) 320 (13.1) 1 (< 0.1) 8 (0.3)
Edema* 164 (6.7) 160 (6.5) 3 (0.1) 1 (< 0.1)
Weight decrease 140 (5.7) 129 (5.3) 8 (0.3) 5 (0.2)
Osteoporosis** 126 (5.1) 67 (2.7) 10 (0.4) 5 (0.2)
Back pain 125 (5.1) 136 (5.6) 7 (0.3) 11 (0.4)
Bone pain 123 (5.0) 109 (4.5) 6 (0.2) 4 (0.2)
Depression 119 (4.9) 114 (4.7) 16 (0.7) 14 (0.6)
Vaginal irritation* 112 (4.6) 77 (3.1) 2 (< 0.1) 2 (< 0.1)
Headache* 105 (4.3) 94 (3.8) 8 (0.3) 4 (0.2)
Pain in extremity 103 (4.2) 79 (3.2) 6 (0.2) 4 (0.2)
Osteopenia* 87 (3.6) 76 (3.1) 0 - 3 (0.1)
Dizziness/light-headedness* 84 (3.4) 80 (3.3) 1 (< 0.1) 6 (0.2)
Alopecia 83 (3.4) 84 (3.4) - - - -
Vomiting* 80 (3.3) 80 (3.3) 3 (0.1) 5 (0.2)
Cataract* 49 (2.0) 54 (2.2) 16 (0.7) 17 (0.7)
Constipation* 49 (2.0) 71 (2.9) 3 (0.1) 1 (< 0.1)
Myocardial infarction1 42 (1.7) 28 (1.1) - - - -
Breast pain* 37 (1.5) 43 (1.8) 1 (< 0.1) - -
Anorexia* 20 (0.8) 20 (0.8) 1 (< 0.1) 1 (< 0.1)
Endometrial proliferation disorders* 14 (0.6) 86 (3.5) 0 - 14 (0.6)
Ovarian cyst* 11 (0.4) 18 (0.7) 4 (0.2) 4 (0.2)
Endometrial hyperplasia/cancer**1 11 (0.4) 72 (2.9) - - - -
Endometrial hyperplasia/cancer**,3 6/1909 (0.3) 57/1943 (2.9) - - - -
Other endometrial disorders* 2 (< 0.1) 3 (0.1) 0 - 0 -
Myocardial infarction**2 24 (1.0) 12 (0.5) - - - -
Myocardial ischemia 6 (0.2) 9 (0.4) - - - -
Cerebrovascular accident/TIA**1 74 (3.0) 68 (2.8) - - - -
Cerebrovascular accident/TIA**2 51 (2.1) 47 (1.9) - - - -
Angina requiring surgery**1 35 (1.4) 33 (1.3) - - - -
Angina requiring surgery**2 25 (1.0) 25 (1.0) - - - -
Thromboembolic event**1 79 (3.2) 113 (4.6) - - - -
Thromboembolic event**2 51 (2.1) 89 (3.6) - - - -
Cardiac failure1 39 (1.6) 34 (1.4) - - - -
Cardiac failure2 27 (1.1) 15 (0.6) - - - -
Hypertension1 160 (6.5) 175 (7.2) - - - -
Hypertension2 138 (5.6) 139 (5.7) - - - -
Other cardiovascular**1 172 (7.0) 174 (7.1) - - - -
Other cardiovascular**2 120 (4.9) 119 (4.9) - - - -
Second primary malignancy1 129 (5.3) 150 (6.1) - - - -
Second primary malignancy2 54 (2.2) 79 (3.2) - - - -
* Target events pre-specified for analysis
** Events pre-printed on CRF
1At median follow-up of 96 months (i.e. any time after randomization) for Femara (range up to 144 months) and 95 months for tamoxifen (range up to 143 months )
2At median treatment duration of 60 months (i.e. during treatment + 30 days after discontinuation of treatment) for Femara and tamoxifen (range up to 68 months)
3Excluding women who had undergone hysterectomy before study entry
TIA = Transient ischemic attack
Note: Cardiovascular events (including cerebrovascular and thromboembolic events), skeletal and urogenital/endometrial events and second primary malignancies were collected life -long. All of these events were assumed to be of CTC Grade 3 to 5 and were not individually graded

When considering all grades during study treatment, a higher incidence of events was seen for Femara regarding fractures (10.1% vs 7.1%), myocardial infarctions (1.0% vs 0.5%), and arthralgia (25.2% vs 20.4%) (Femara vs tamoxifen respectively). A higher incidence was seen for tamoxifen regarding thromboembolic events (2.1% vs 3.6%), endometrial hyperplasia/cancer (0.3% vs 2.9%), and endometrial proliferation disorders (0.3% vs 1.8%) (Femara vs tamoxifen respectively).

At a median follow-up of 96 months, a higher incidence of events was seen for Femara (14.7%) than for tamoxifen (11.4%) regarding fractures. A higher incidence was seen for tamoxifen compared to Femara regarding thromboembolic events (4.6% vs 3.2%), and endometrial hyperplasia or cancer (2.9% vs 0.4%) (tamoxifen vs Femara, respectively).

Bone Study

Results of a safety trial in 263 postmenopausal women with resected receptor positive early breast cancer in the adjuvant setting comparing the effect on lumbar spine (L2-L4) BMD of adjuvant treatment with letrozole to that with tamoxifen showed at 24 months a median decrease in lumbar spine BMD of 4.1% in the letrozole arm compared to a median increase of 0.3% in the tamoxifen arm (difference = 4.4%) (P < 0.0001). No patients with a normal BMD at baseline became osteoporotic over the 2 years and only 1 patient with osteopenia at baseline (T score of -1.9) developed osteoporosis during the treatment period (assessment by central review). The results for total hip BMD were similar, although the differences between the two treatments were less pronounced. During the 2 year period, fractures were reported by 4 of 103 patients (4%) in the letrozole arm, and 6 of 97 patients (6%) in the tamoxifen arm.

Lipid Study

In a safety trial in 263 postmenopausal women with resected receptor positive early breast cancer at 24 months comparing the effects on lipid profiles of adjuvant letrozole to tamoxifen, 12% of patients on letrozole had at least one total cholesterol value of a higher CTCAE grade than at baseline compared with 4% of patients on tamoxifen. In another postapproval randomized, multicenter, open label, study of letrozole vs anastrozole in the adjuvant treatment of postmenopausal women with hormone receptor and node positive breast cancer (FACE, NCT00248170), the median duration of treatment was 60 months for both treatment arms. Table 2 describes adverse reactions (Grades 1-4 and Grades 3-4) irrespective of relationship to study treatment in the adjuvant study (safety population).

Table 2: Adverse Reactions (CTC Grades 1-4), Occurring in at least 5% of Patients in Either Treatment Arm, by Preferred Term (Safety set)

Adverse Reactions Letrozole
N = 2049
n (%)
Anastrozole
N = 2062
n (%)
Grade 3/4
n (%)
All Grades
n (%)
Grade 3/4
n (%)
All Grades
n (%)
Patients with at least one AR 628 (30.6) 2049 (100.0) 591 (28.7) 2062 (100.0)
Arthralgia 80 (3.9) 987 (48.2) 69 (3.3) 987 (47.9)
Hot flush 17 (0.8) 666 (32.5) 9 (0.4) 666 (32.3)
Fatigue 8 (0.4) 345 (16.8) 10 (0.5) 343 (16.6)
Osteoporosis 5 (0.2) 223 (10.9) 11 (0.5) 225 (10.9)
         
Myalgia 16 (0.8) 233 (11.4) 15 (0.7) 212 (10.3)
Back pain 11 (0.5) 212 (10.3) 17 (0.8) 193 (9.4)
Osteopenia 4 (0.2) 203 (9.9) 1 (0.0) 173 (8.4)
Pain in extremity 9 (0.4) 168 (8.2) 3 (0.1) 174 (8.4)
Lymphoedema 5 (0.2) 159 (7.8) 2 (0.1) 179 (8.7)
Insomnia 7 (0.3) 160 (7.8) 3 (0.1) 149 (7.2)
Hypercholesterolaemia 2 (0.1) 155 (7.6) 1 (0.0) 151 (7.3)
Hypertension 25 (1.2) 156 (7.6) 20 (1.0) 149 (7.2)
         
Depression 16 (0.8) 147 (7.2) 13 (0.6) 137 (6.6)
Bone pain 10 (0.5) 138 (6.7) 9 (0.4) 122 (5.9)
Nausea 6 (0.3) 137 (6.7) 5 (0.2) 152 (7.4)
Headache 3 (0.1) 130 (6.3) 5 (0.2) 168 (8.1)
Alopecia 2 (0.1) 127 (6.2) 0 (0.0) 134 (6.5)
Musculoskeletal pain 6 (0.3) 123 (6.0) 9 (0.4) 147 (7.1)
Radiation skin injury 11 (0.5) 120 (5.9) 6 (0.3) 88 (4.3)
Dyspnoea 16 (0.8) 118 (5.8) 10 (0.5) 96 (4.7)
Cough 1 (0.0) 106 (5.2) 1 (0.0) 120 (5.8)
Musculoskeletal stiffness 2 (0.1) 102 (5.0) 2 (0.1) 84 (4.1)
Dizziness 2 (0.2) 94 (4.6) 7 (0.3) 109 (5.3)

The following adverse reactions were also identified in less than 5% of the 2049 patients treated with letrozole and not included in the table: fall, vertigo, hyperbilirubinemia, jaundice, and chest pain.

Extended Adjuvant Treatment Of Early Breast Cancer, Median Treatment Duration Of 24 Months

In study MA-17, the median duration of extended adjuvant treatment was 24 months and the median duration of follow-up for safety was 28 months for patients receiving Femara and placebo.

Table 3 describes the adverse reactions occurring at a frequency of at least 5% in any treatment group during treatment. Most adverse reactions reported were Grade 1 and Grade 2 based on the CTC Version 2.0. In the extended adjuvant setting, the reported drug-related adverse reactions that were significantly different from placebo were hot flashes, arthralgia/arthritis, and myalgia.

Table 3: Adverse Reactions Occurring in at least 5% of Patients in either Treatment Arm

  Number (%) of Patients with Grade 1-4
Adverse Reactions
Number (%) of Patients with Grade 3-4
Adverse Reactions
Femara
N = 2563
Placebo
N = 2573
Femara
N = 2563
Placebo
N = 2573
Any Adverse Reactions 2232 (87.1) 2174 (84.5) 419 (16.3) 389 (15.1)
Vascular Disorders 1375 (53.6) 1230 (47.8) 59 (2.3) 74 (2.9)
  Flushing 1273 (49.7) 1114 (43.3) 3 (0.1) 0
General Disorders 1154 (45) 1090 (42.4) 30 (1.2) 28 (1.1)
  Asthenia 862 (33.6) 826 (32.1) 16 (0.6) 7 (0.3)
  Edema NOS 471 (18.4) 416 (16.2) 4 (0.2) 3 (0.1)
Musculoskeletal Disorders 978 (38.2) 836 (32.5) 71 (2.8) 50 (1.9)
  Arthralgia 565 (22) 465 (18.1) 25 (1) 20 (0.8)
  Arthritis NOS 173 (6.7) 124 (4.8) 10 (0.4) 5 (0.2)
  Myalgia 171 (6.7) 122 (4.7) 8 (0.3) 6 (0.2)
  Back Pain 129 (5) 112 (4.4) 8 (0.3) 7 (0.3)
Nervous System Disorders 863 (33.7) 819 (31.8) 65 (2.5) 58 (2.3)
  Headache 516 (20.1) 508 (19.7) 18 (0.7) 17 (0.7)
  Dizziness 363 (14.2) 342 (13.3) 9 (0.4) 6 (0.2)
Skin Disorders 830 (32.4) 787 (30.6) 17 (0.7) 16 (0.6)
  Sweating Increased 619 (24.2) 577 (22.4) 1 (< 0.1) 0
Gastrointestinal Disorders 725 (28.3) 731 (28.4) 43 (1.7) 42 (1.6)
  Constipation 290 (11.3) 304 (11.8) 6 (0.2) 2 (< 0.1)
  Nausea 221 (8.6) 212 (8.2) 3 (0.1) 10 (0.4)
  Diarrhea NOS 128 (5) 143 (5.6) 12 (0.5) 8 (0.3)
Metabolic Disorders 551 (21.5) 537 (20.9) 24 (0.9) 32 (1.2)
  Hypercholesterolemia 401 (15.6) 398 (15.5) 2 (< 0.1) 5 (0.2)
Reproductive Disorders 303 (11.8) 357 (13.9) 9 (0.4) 8 (0.3)
  Vaginal Hemorrhage 123 (4.8) 171 (6.6) 2 (< 0.1) 5 (0.2)
  Vulvovaginal Dryness 137 (5.3) 127 (4.9) 0 0
Psychiatric Disorders 320 (12.5) 276 (10.7) 21 (0.8) 16 (0.6)
  Insomnia 149 (5.8) 120 (4.7) 2 (< 0.1) 2 (< 0.1)
Respiratory Disorders 279 (10.9) 260 (10.1) 30 (1.2) 28 (1.1)
  Dyspnea 140 (5.5) 137 (5.3) 21 (0.8) 18 (0.7)
Investigations 184 (7.2) 147 (5.7) 13 (0.5) 13 (0.5)
Infections and Infestations 166 (6.5) 163 (6.3) 40 (1.6) 33 (1.3)
Renal Disorders 130 (5.1) 100 (3.9) 12 (0.5) 6 (0.2)

Based on a median follow-up of patients for 28 months,the incidence of clinical fractures from the core randomized study in patients who received Femara was 5.9% (152) and placebo was 5.5% (142). The incidence of self-reported osteoporosis was higher in patients who received Femara 6.9% (176) than in patients who received placebo 5.5% (141). Bisphosphonates were administered to 21.1% of the patients who received Femara and 18.7% of the patients who received placebo.

The incidence of cardiovascular ischemic events from the core randomized study was comparable between patients who received Femara 6.8% (175) and placebo 6.5% (167).

A patient-reported measure that captures treatment impact on important symptoms associated with estrogen deficiency demonstrated a difference in favor of placebo for vasomotor and sexual symptom domains.

Bone Substudy: [see WARNINGS AND PRECAUTIONS]

Lipid Substudy: In the extended adjuvant setting, based on a median duration of follow-up of 62 months, there was no significant difference between Femara and placebo in total cholesterol or in any lipid fraction at any time over 5 years. Use of lipid lowering drugs or dietary management of elevated lipids was allowed [see WARNINGS AND PRECAUTIONS].

Updated Analysis, Extended Adjuvant Treatment Of Early Breast Cancer, Median Treatment Duration Of 60 Months

The extended adjuvant treatment trial (MA-17) was unblinded early [see ADVERSE REACTIONS]. At the updated (final analysis), overall the side effects seen were consistent to those seen at a median treatment duration of 24 months.

During treatment or within 30 days of stopping treatment (median duration of treatment 60 months) a higher rate of fractures was observed for Femara (10.4%) compared to placebo (5.8%), as also a higher rate of osteoporosis (Femara 12.2% vs placebo 6.4%).

Based on 62 months median duration of follow-up in the randomized letrozole arm in the safety population the incidence of new fractures at any time after randomization was 13.3% for letrozole and 7.8% for placebo. The incidence of new osteoporosis was 14.5% for letrozole and 7.8% for placebo.

During treatment or within 30 days of stopping treatment (median duration of treatment 60 months), the incidence of cardiovascular events was 9.8% for Femara and 7.0% for placebo.

Based on 62 months median duration of follow-up in the randomized letrozole arm in the safety population the incidence of cardiovascular disease at any time after randomization was 14.4% for letrozole and 9.8% for placebo.

Lipid substudy

In the extended adjuvant setting (MA-17), based on a median duration of follow-up of 62 months, there was no significant difference between Femara and placebo in total cholesterol or in any lipid fraction over 5 years. Use of lipid lowering drugs or dietary management of elevated lipids was allowed [see WARNINGS AND PRECAUTIONS].

First-Line Treatment Of Advanced Breast Cancer

In study P025 a total of 455 patients were treated for a median time of exposure of 11 months in the Femara arm (median 6 months in the tamoxifen arm). The incidence of adverse reactions was similar for Femara and tamoxifen. The most frequently reported adverse reactions were bone pain, hot flushes, back pain, nausea, arthralgia and dyspnea. Discontinuations for adverse reactions other than progression of tumor occurred in 10/455 (2%) of patients on Femara and in 15/455 (3%) of patients on tamoxifen.

Adverse reactions that were reported in at least 5% of the patients treated with Femara 2.5 mg or tamoxifen 20 mg in the first-line treatment study are shown in Table 4.

Table 4: Adverse Reactions Occurring in at least 5% of Patients in either Treatment Arm

Adverse Reactions Femara
2.5 mg
(N = 455)
%
Tamoxifen
20 mg
(N = 455)
%
General Disorders
  Fatigue 13 13
  Chest Pain 8 9
  Edema Peripheral 5 6
  Pain NOS 5 7
  Weakness 6 4
Investigations
  Weight Decreased 7 5
Vascular Disorders
  Hot Flushes 19 16
  Hypertension 8 4
Gastrointestinal Disorders
  Nausea 17 17
  Constipation 10 11
  Diarrhea 8 4
  Vomiting 7 8
Infections/Infestations
  Influenza 6 4
  Urinary Tract Infection NOS 6 3
Injury, Poisoning and Procedural Complications
  Post-Mastectomy Lymphedema 7 7
Metabolism and Nutrition Disorders
  Anorexia 4 6
Musculoskeletal and Connective Tissue Disorders
  Bone Pain 22 21
  Back Pain 18 19
  Arthralgia 16 15
  Pain in Limb 10 8
Nervous System Disorders
  Headache NOS 8 7
Psychiatric Disorders
  Insomnia 7 4
Reproductive System and Breast Disorders
  Breast Pain 7 7
Respiratory, Thoracic and Mediastinal Disorders
  Dyspnea 18 17
  Cough 13 13
  Chest Wall Pain 6 6

Other less frequent (less than or equal to 2%) adverse reactions considered consequential for both treatment groups, included peripheral thromboembolic events, cardiovascular events, and cerebrovascular events. Peripheral thromboembolic events included venous thrombosis, thrombophlebitis, portal vein thrombosis and pulmonary embolism. Cardiovascular events included angina, myocardial infarction, myocardial ischemia, and coronary heart disease. Cerebrovascular events included transient ischemic attacks, thrombotic or hemorrhagic strokes and development of hemiparesis.

Second-Line Treatment Of Advanced Breast Cancer

Study discontinuations in the megestrol acetate comparison study (AR/BC2) for adverse reactions other than progression of tumor were 5/188 (2.7%) on Femara 0.5 mg, in 4/174 (2.3%) on Femara 2.5 mg, and in 15/190 (7.9%) on megestrol acetate. There were fewer thromboembolic events at both Femara doses than on the megestrol acetate arm (0.6% vs 4.7%). There was also less vaginal bleeding (0.3% vs 3.2%) on Femara than on megestrol acetate. In the aminoglutethimide comparison study (AR/BC3), discontinuations for reasons other than progression occurred in 6/193 (3.1%) on 0.5 mg Femara, 7/185 (3.8%) on 2.5 mg Femara, and 7/178 (3.9%) of patients on aminoglutethimide.

Comparisons of the incidence of adverse reactions revealed no significant differences between the high and low dose Femara groups in either study. Most of the adverse reactions observed in all treatment groups were mild to moderate in severity and it was generally not possible to distinguish adverse reactions due to treatment from the consequences of the patient’s metastatic breast cancer, the effects of estrogen deprivation, or intercurrent illness.

Adverse reactions that were reported in at least 5% of the patients treated with Femara 0.5 mg, Femara 2.5 mg, megestrol acetate, or aminoglutethimide in the two controlled trials AR/BC2 and AR/BC3 are shown in Table 5.

Table 5: Adverse Reactions Occurring at a Frequency of at Least 5% of Patients in Either Treatment Arm

Adverse Reactions Pooled
Femara
2.5 mg
(N = 359)
%
Pooled
Femara
0.5 mg
(N = 380)
%
Megestrol
Acetate
160 mg
(N = 189)
%
Aminoglutethimide
500 mg
(N = 178)
%
Body as a Whole
  Chest Pain 6 3 7 3
  Peripheral Edema1 5 5 8 3
  Asthenia 4 5 4 5
  Weight Increase 2 2 9 3
Cardiovascular
  Hypertension 5 7 5 6
Digestive System
  Nausea 13 15 9 14
  Vomiting 7 7 5 9
  Constipation 6 7 9 7
  Diarrhea 6 5 3 4
  Pain-Abdominal 6 5 9 8
  Anorexia 5 3 5 5
  Dyspepsia 3 4 6 5
Infections/Infestations
  Viral Infection 6 5 6 3
Lab Abnormality
  Hypercholesterolemia 3 3 0 6
Musculoskeletal System
  Musculoskeletal2 21 22 30 14
  Arthralgia 8 8 8 3
Nervous System
  Headache 9 12 9 7
  Somnolence 3 2 2 9
  Dizziness 3 5 7 3
Respiratory System
  Dyspnea 7 9 16 5
  Coughing 6 5 7 5
Skin and Appendages
  Hot Flushes 6 5 4 3
  Rash3 5 4 3 12
  Pruritus 1 2 5 3
1Includes peripheral edema, leg edema, dependent edema, edema
2Includes musculoskeletal pain, skeletal pain, back pain, arm pain, leg pain
3Includes rash, erythematous rash, maculopapular rash, psoriasiform rash, vesicular rash

Other less frequent (less than 5%) adverse reactions considered consequential and reported in at least 3 patients treated with Femara, included hypercalcemia, fracture, depression, anxiety, pleural effusion, alopecia, increased sweating and vertigo.

First And Second-Line Treatment Of Advanced Breast Cancer

In the combined analysis of the first- and second-line metastatic trials and postmarketing experiences other adverse reactions that were reported were cataract, eye irritation, palpitations, cardiac failure, tachycardia, dysesthesia (including hypesthesia/paresthesia), arterial thrombosis, memory impairment, irritability, nervousness, urticaria, increased urinary frequency, leukopenia, stomatitis cancer pain, pyrexia, vaginal discharge, appetite increase, dryness of skin and mucosa (including dry mouth), and disturbances of taste and thirst.

Postmarketing Experience

The following adverse reactions have been identified during postapproval use of Femara. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

  • Eye Disorders: blurred vision
  • Hepatobiliary Disorders: increased hepatic enzymes, hepatitis
  • Immune System Disorders: anaphylactic reactions, hypersensitivity reactions
  • Nervous System Disorders: carpal tunnel syndrome, trigger finger
  • Pregnancy: spontaneous abortions, congenital birth defects
  • Skin and subcutaneous disorders: angioedema, toxic epidermal necrolysis, erythema multiforme

Read the entire FDA prescribing information for Femara (Letrozole)

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© Femara Patient Information is supplied by Cerner Multum, Inc. and Femara Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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