Genox (Tamoxifen Citrate)
Complete patient guide for uses, dosage, side effects, and safety information
Prescription RequiredQuick Facts
What Is Genox Used For?
Genox contains tamoxifen citrate, which blocks the actions of estrogen, a natural female hormone that can help certain types of breast cancer cells grow.
Primary Uses
Genox is used to either treat breast cancer or reduce the risk of breast cancer occurring if you are at increased risk of developing breast cancer.
How It Works
Genox works by blocking the actions of estrogen. In some types of breast cancer, estrogen can help cancer cells to grow, so blocking estrogen helps prevent this growth.
Good to know: Genox is not addictive.
How to Take Genox
Take Genox exactly as prescribed by your doctor. Swallow the tablets whole with a full glass of water at about the same time each day.
Dosage Instructions
The usual starting dose is 20 mg once a day. Your doctor may increase this dose to 40 mg a day, depending on your condition and how you respond to the medicine. Patients with liver problems may need smaller doses. Do not chew or crush the tablets. Genox can be taken with or without food.
What If You Miss a Dose?
If it is almost time for your next dose, skip the dose you missed and take your next dose when you are meant to. Otherwise, take the missed dose as soon as you remember, and then go back to taking your tablets as you would normally.
Important: Do not take a double dose to make up for the dose you missed.
Available Tablet Strengths
Side Effects
Like all medications, this medicine can cause side effects. Most are mild and temporary, but some require medical attention.
Common Side Effects
These side effects occur relatively frequently and usually don’t require emergency care:
- depression
- hot flushes
- nausea and vomiting
- unusual vaginal discharge
- changes in periods
- itching around the vagina
- diarrhea or constipation
- headache, dizziness or light headedness
- hair thinning or hair loss
- leg cramps
Seek immediate medical attention if you experience:
- skin rash, itching, hives or peeling skin
- swelling of face, lips, tongue and/or throat, difficulty swallowing or breathing
- wheezing with difficulty breathing
- sudden weakness or paralysis of arms or legs
- sudden difficulty speaking, walking, holding things or thinking
- unusual pain or pressure around pelvis or bones
- excessive thirst
- swelling of hands, ankles and feet
- changes in vision
- lumps anywhere in the body
- unusual tiredness, shortness of breath and dizziness when exercising
- frequent infection, fever, severe chills, sore throat or mouth ulcers
- unexplained bruising
- yellowing of skin or eyes, dark colored urine
Important Warnings
There are several important warnings to be aware of before taking Genox, especially regarding serious side effects and contraindications.
Who Should Not Take Genox
Do not take Genox if you are allergic to tamoxifen citrate or any ingredients, allergic to other anti-estrogen medicines, taking blood clot prevention medicines like warfarin, have had deep vein thrombosis or pulmonary embolus, or if the packaging is damaged.
Medical Conditions to Discuss
Tell your doctor if you have: hereditary angioedema, unusual vaginal bleeding or discharge, blood disorders, liver problems, deep vein thrombosis or pulmonary embolus, heart conditions including rhythm problems, or if you are a premenopausal woman (as bone mineral loss may occur).
Pregnancy and Breastfeeding
Do not take Genox if you are pregnant or planning to become pregnant. Do not get pregnant while taking Genox and for nine months after stopping. Men should not father a child while taking Genox and for six months after stopping. Do not breastfeed while taking Genox.
Serious Risk Warning: Genox therapy may be associated with serious side effects such as deep vein thrombosis, pulmonary embolus, and uterine cancer. In some women, these events were fatal.
Drug Interactions
Some medicines may interfere with Genox and affect how it works. Always tell your doctor about all medicines you are taking.
Important: Genox should not be taken with aromatase inhibitors such as anastrozole, letrozole or exemestane.
- oral contraceptives (‘the pill’)
- hormone replacement therapy
- other medicines used to treat cancer
- medicines used to prevent blood clots (e.g. warfarin)
- rifampicin (an antibiotic)
- chemotherapy
- aromatase inhibitors (anastrozole, letrozole, exemestane)
Alcohol & Driving
Be careful when driving or operating machinery until you know how Genox affects you.
Alcohol
No specific alcohol warnings mentioned in the source material.
Driving and Operating Machinery
Be careful driving or operating machinery until you know how Genox affects you. Some patients may experience dizziness, fatigue or light headedness. If this occurs, do not drive, operate machinery or do anything else that could be dangerous.
Temperature Regulation
No specific temperature regulation warnings mentioned in the source material.
Storage
Keep your Genox tablets in the blister pack until it is time to take them. Store in a cool, dry place where the temperature stays below 25°C. Keep away from moisture, heat or sunlight. Do not store in the bathroom, near a sink, in the car or on window sills. Keep where young children cannot reach it – a locked cupboard at least one-and-a-half metres above the ground is recommended.
Overdose Information
If you think that you or anyone else has taken too much Genox, urgent medical attention may be needed. Immediately phone the Poisons Information Centre (13 11 26) for advice, contact your doctor, or go to the Emergency Department at your nearest hospital. Do this even if there are no signs of discomfort or poisoning. There have been reports of heart rhythm problems associated with an overdose of this medicine.
Frequently Asked Questions
Keep taking Genox for as long as your doctor recommends. Do not stop taking Genox or lower the dosage unless you have discussed this with your doctor.
Yes, Genox tablets can be taken with or without food. Swallow the tablets whole with a glass of water at about the same time each day.
No, Genox is not addictive.
If it is almost time for your next dose, skip the missed dose and take your next dose when you are meant to. Otherwise, take the missed dose as soon as you remember. Do not take a double dose to make up for the missed dose.
If you go into hospital, please let the medical staff know that you are taking Genox. Tell any other doctors, dentists and pharmacists who are treating you that you are taking Genox.
Yes, you will need to have regular gynecological check-ups while taking Genox. Your doctor may also order regular blood tests to check your calcium levels, white blood cell and platelet counts.
Tell your doctor immediately if you notice any unusual gynecological symptoms, especially vaginal bleeding or discharge, even if it occurs after treatment with Genox has stopped. This could be a sign of serious side effects.
Important Disclaimer
This information is intended for general educational purposes only and should not be considered medical advice. Always consult your healthcare provider or pharmacist before starting, stopping, or changing any medication.
If you think you may have a medical emergency, call your doctor or emergency services immediately.