MEREX 500MG INJECTION
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About MEREX 500MG INJECTION
MEREX 500MG INJECTION is a prescription injection used to treat severe rheumatoid arthritis, severe psoriasis, and certain types of cancer. It is prescribed when other standard treatments have not provided sufficient relief or when rapid disease control is necessary.
To achieve the best results, this medication must be used with strict consistency. It is typically injected only once a week, and keeping a regular, weekly schedule is crucial for both safety and effectiveness. Since it is an injection, food intake does not alter how your body processes it, but maintaining a balanced diet, avoiding alcohol, and limiting sun exposure can help support your body during treatment.
While highly effective, MEREX 500MG INJECTION can cause some common side effects, such as mild nausea, temporary hair thinning, or minor mouth sores. However, you must contact your healthcare provider immediately if you experience serious symptoms like a high fever, persistent cough, or yellowing of your skin or eyes.
Do not take this if you are pregnant, planning to become pregnant, or breastfeeding, as it can cause severe harm to an unborn baby. Before starting, talk to your doctor if you have a history of liver disease, kidney problems, active infections, or blood disorders.
MEREX 500MG INJECTION can interact with alcohol, smoking, and certain pain relievers, which can increase the risk of serious liver or lung complications. Special care and close monitoring are required for elderly individuals, as their kidneys may process the medication more slowly. Talk to your doctor or pharmacist to discuss your full list of medications before starting treatment.
Uses of MEREX 500MG INJECTION
MEREX 500MG INJECTION helps control certain autoimmune diseases and cancers by slowing the growth of abnormal cells and reducing immune system activity. Your doctor may recommend it for the following conditions:
- Rheumatoid Arthritis: Helps reduce joint pain, swelling, and stiffness by calming an overactive immune system, preventing long-term joint damage.
- Severe Psoriasis: Slows down the rapid growth of skin cells, helping to clear up red, scaly patches and restore comfort.
- Certain Cancers: Slows or stops the growth of rapidly dividing cancer cells in the body.
Key Benefits
MEREX 500MG INJECTION helps control disease activity, relieve symptoms, and improve quality of life in people with certain autoimmune conditions and cancers. Key benefits include:
- Relieves joint symptoms: Helps reduce joint pain, swelling, and morning stiffness, making daily activities easier and more comfortable.
- Helps protect joints: By controlling the underlying disease, it helps reduce the risk of long-term joint damage and physical deformity.
- Improves skin health: Helps clear painful or itchy psoriatic plaques, improving skin texture and reducing discomfort.
- Convenient treatment schedule: As a once-weekly injection, it offers a convenient dosing routine that may help improve treatment adherence.
- Report the itching to your doctor immediately; they may need to change your medication or dosage.
- Use a cool, damp cloth on the itchy area to help soothe and calm the skin, reducing itching and inflammation.
- Keep your skin hydrated and healthy with gentle, fragrance-free moisturizers.
- Try not to scratch, as this can worsen the itching and irritate your skin.
- If your doctor prescribes, you can take oral medications or apply topical creams or ointments to help relieve itching.
- Track your itching symptoms and follow your doctor's guidance to adjust your treatment plan if needed. If the itching persists, consult your doctor for further advice.
- Inform Your Doctor: Notify your doctor immediately about your diarrhoea symptoms. This allows them to adjust your medication or provide guidance on managing side effects.
- Stay Hydrated: Drink plenty of fluids to replace lost water and electrolytes. Choose water, clear broth, and electrolyte-rich drinks. Avoid carbonated or caffeinated beverages to effectively rehydrate your body.
- Follow a Bland Diet: Eat easy-to-digest foods to help firm up your stool and settle your stomach. Try incorporating bananas, rice, applesauce, toast, plain crackers, and boiled vegetables into your diet.
- Avoid Trigger Foods: Steer clear of foods that can worsen diarrhoea, such as spicy, fatty, or greasy foods, high-fibre foods, and dairy products (especially if you're lactose intolerant).
- Practice Good Hygiene: Maintain good hygiene to prevent the spread of infection. To stay healthy, wash your hands frequently, clean and disinfect surfaces regularly, and avoid exchanging personal belongings with others.
- Take Anti-Diarrheal Medications: If your doctor advises, anti-diarrheal medications such as loperamide might help manage diarrhoea symptoms. Always follow your doctor's directions.
- Keep track of your diarrhoea symptoms. If they don't get better or worse or are accompanied by severe stomach pain, blood, or dehydration signs (like extreme thirst or dark urine), seek medical help.
- Boost your immunity by including immune rich foods in your diet and always remember to stay hydrated.
- Get sufficient sleep and manage stress which helps in improving white blood cell count.
- Consult your doctor for an effective treatment to improve the blood cell count and get regular body check up to monitor changes in the count.
- Try to prevent the factors that cause a decrease in white blood cells which may lead to impaired immunity.
- Consult your doctor if you experience skin redness, itching, or irritation after taking medication.
- Your doctor may adjust your treatment plan by changing your medication or providing guidance on managing your erythema symptoms.
- Your doctor may recommend or prescribe certain medications to help alleviate symptoms.
- Apply cool compresses or calamine lotion to the affected skin area to reduce redness and itching.
- Stay hydrated by drinking plenty of water to help alleviate symptoms and keep your skin hydrated.
- Monitor your skin condition closely and promptly report any changes, worsening symptoms, or concerns to your healthcare provider.
Directions for Use
- Follow your doctor’s instructions on the dosage and timing of this medication to ensure safe and effective use.
- MEREX 500MG INJECTION will be administered by the doctor.
- Do not self-administer.
How MEREX 500MG INJECTION Works
Alcohol
Unsafe
You are recommended to avoid alcohol consumption while taking MEREX 500MG INJECTION.
Pregnancy
Unsafe
MEREX 500MG INJECTION may cause serious birth defects. It is not recommended to take MEREX 500MG INJECTION while you are pregnant.
Breast Feeding
Unsafe
MEREX 500MG INJECTION passes into breast milk. Avoid breastfeeding whilst on treatment with MEREX 500MG INJECTION and for at least 1 week after the last dose.
Driving
Caution
MEREX 500MG INJECTION may cause dizziness and tiredness; do not drive or operate heavy machinery until you know how MEREX 500MG INJECTION affects you.
Liver
Caution
Please consult your doctor if you have liver impairment before receiving MEREX 500MG INJECTION.
Kidney
Caution
Please consult your doctor if you have kidney impairment before receiving MEREX 500MG INJECTION.
Children
Caution
The efficacy and safety of MEREX 500MG INJECTION in children have been established in polyarticular-course juvenile rheumatoid arthritis and cancer chemotherapy. Please consult your doctor if you have any concerns regarding the usage of MEREX 500MG INJECTION in children.
Heart
Caution
MEREX 500MG INJECTION can be used in heart patients and may even provide cardiovascular benefits. However, it should be administered under medical supervision due to potential side effects and drug interactions.
Geriatrics
Caution
MEREX 500MG INJECTION can be used in geriatric patients, but with caution due to increased sensitivity to side effects like liver toxicity and bone marrow suppression. Regular monitoring and dose adjustments are essential to ensure safe use.
What if I have taken an overdose of MEREX 500MG INJECTION
Diet & Lifestyle Advise
- Take Folic Acid: Your doctor will likely prescribe a folic acid supplement. This B-vitamin helps protect healthy cells and reduces common side effects like mouth sores and nausea. Take it exactly as directed, usually on the days you do not receive your injection.
- Avoid Alcohol: Do not drink alcohol while using this medicine, as the combination significantly increases the risk of severe liver damage.
- Protect Your Skin: This medication makes your skin highly sensitive to sunlight. Wear protective clothing, a wide-brimmed hat, and apply a broad-spectrum sunscreen with SPF 30 or higher when outdoors.
- Stay Well-Hydrated: Drink plenty of water, especially on the day of your injection, to help your kidneys flush the medication out of your system safely.
- Practice Good Hygiene: Because this medicine can lower your white blood cell count and weaken your immune system, wash your hands frequently and avoid close contact with individuals who have active infections.

Have a query?
How Soon It Starts Working
The time required for MEREX 500MG INJECTION to start to work: MEREX 500MG INJECTION ideally shows its action within 30 to 60 minutes after administration.
The time for which the effects of MEREX 500MG INJECTION last: The effect of MEREX 500MG INJECTION lasts for 9 to 30 hours at a low dose and 24 to 45 hours at a high dose.
What if you forget to take MEREX 500MG INJECTION
Storage
Keep Refrigerated. Do not freeze.Prepaid payment required.
Drug Warnings
- Inspect the Liquid: Always check the solution before injecting. It should be clear and yellow to brown-yellow. Do not use it if it is cloudy, contains floating particles, or looks discoloured.
- Rotate Injection Sites: Choose a different spot (such as alternating thighs or sides of the abdomen) for each weekly injection to reduce skin irritation.
- Never Reuse Needles: Use a sterile needle and syringe or pre-filled pen only once, then discard it immediately in your sharps container to prevent infections.
- Avoid Live Vaccines: Talk to your doctor before getting any immunisations. Avoid live vaccines (such as those for shingles or yellow fever) while on this treatment, as your immune system may not react safely to them.
- Strict Weekly Schedule: Always remember that this medication is injected only once a week. Taking it daily can lead to severe, life-threatening complications.
Drug-Drug Interactions
Drug-Drug Interaction Summary:
- Pain Relievers: Using certain pain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), alongside this injection can increase the levels of the medicine in your blood, raising the risk of severe side effects.
- Antibiotics: Certain antibiotics (such as penicillins or trimethoprim) can interfere with how your kidneys clear this medicine, increasing its toxicity.
- Acid-Reflux Medications: Proton pump inhibitors (PPIs) may delay the clearance of this medicine from your body, potentially increasing the risk of adverse reactions.
Drug-Drug Interactions
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Co-administration of Etretinate with Merex 500mg Injection may increase the risk or severity of liver problems.
How to manage the interaction:
Taking Etretinate with Merex 500mg Injection is generally avoided as it can possibly result in an interaction, it can be taken if a doctor has advised it. Do not stop using any medications without talking to a doctor.
Co-administration of Sirolimus with Merex 500mg Injection can increase the risk or severity of kidney damage.
How to manage the interaction:
Although there is a possible interaction between sirolimus and Merex 500mg Injection, you can take these medicines together if prescribed by a doctor. However, if you experience nausea, vomiting, a decrease in hunger, increased or decreased urine, weight gain or loss that occurs suddenly, fluid retention, swelling, difficulty breathing, muscle pain, fatigue, weakness, dizziness, confusion, and irregular heartbeat, consult a doctor. Do not discontinue any medications without a doctor's advice.
Taking tacrolimus with Merex 500mg Injection may increase the risk of kidney problems.
How to manage the interaction:
Although there is a possible interaction between tacrolimus and Merex 500mg Injection, you can take these medicines together if prescribed by your doctor. However, if you experience any symptoms such as nausea, vomiting, loss of hunger, increased or decreased urination, sudden weight gain or weight loss, fluid retention, swelling, shortness of breath, tiredness, weakness, dizziness. Consult your doctor. Do not stop using any medications without consulting to a doctor.
Coadministration of Tenofovir disoproxil with Merex 500mg Injection may increase the levels and side effects of Tenofovir disoproxil.
How to manage the interaction:
Although there is a possible interaction between tenofovir disoproxil and Merex 500mg Injection, you can take these medicines when prescribed by your doctor. However, if you experience any symptoms such as vomiting, loss of appetite, increased or decreased urination, sudden weight gain or weight loss, breathing difficulty, or dizziness, consult your doctor. Do not stop using any medications without consulting a doctor.
Co-administration of Merex 500mg Injection with Rabeprazole can increase the blood levels and side effects of Merex 500mg Injection.
How to manage the interaction:
Although there is a possible interaction between Rabeprazole and Merex 500mg Injection, you can take these medicines together if prescribed by a doctor. Do not stop using any medications without consulting a doctor.
Co-administration of Merex 500mg Injection with Dexlansoprazole can increase the levels and side effects of Merex 500mg Injection.
How to manage the interaction:
Although there is a possible interaction between Merex 500mg Injection and Dexlansoprazole, you can take these medicines together if prescribed by your doctor. However, if you experience any symptoms such as tiredness, dizziness, fainting, unusual bleeding or bruising, chills, fever, sore throat, or body pains. Consult a doctor immediately. Do not stop using medications without a doctor's advice.
Coadministration of Mefenamic acid with Merex 500mg Injection may increase the blood levels and side effects of Merex 500mg Injection.
How to manage the interaction:
Although there is a possible interaction between mefenamic acid and Merex 500mg Injection, you can take these medicines together if prescribed by your doctor. However, if you experience any symptoms such as nausea, vomiting, diarrhea, rash, appetite loss, joint pain or swelling, yellowing of the skin or eyes, dark urine, breathing difficulty, a dry cough, dizziness or fainting, unusual bruising or bleeding, seizures(fits), mouth sores or ulcers, infection, as well as flu-like symptoms(fever, chills, body pains, sore throat, and weakening of the muscles), consult a doctor immediately. Do not stop using medications without a doctor's advice.
Coadministration of Merex 500mg Injection with piroxicam can increase the levels and side effects.
How to manage the interaction:
Although there is a possible interaction between piroxicam and Merex 500mg Injection, it can be taken if prescribed by a doctor. However, if you experience any symptoms such as mouth ulcers or sores, vomiting, fever, chills, body aches, sore throat, muscle weakness, diarrhea, rash, loss of appetite, joint pain or swelling, yellow discoloration of skin and eyes, dark urine, breathing difficulty, dry cough, paleness, dizziness or fainting, unusual bruising or bleeding, seizures(fits), Consult a doctor. Do not stop using any medications without consulting a doctor.
Co-administration of Merex 500mg Injection with cladribine can increase the risk or severity of developing serious infections.
How to manage the interaction:
Although there is a possible interaction between cladribine and Merex 500mg Injection, you can take these medicines together if prescribed by your doctor. However, if you experience any symptoms such as fever, chills, diarrhea, sore throat, muscle aches, shortness of breath, weight loss, red or inflamed skin, and pain or burning during urination, Consult a doctor. Do not stop using any medications without consulting a doctor.
Co-administration of Meloxicam with Merex 500mg Injection may increase the levels and side effects of Meloxicam.
How to manage the interaction:
Although there is a possible interaction between meloxicam and Merex 500mg Injection, you can take these medicines together if prescribed by a doctor. However, if you experience any symptoms such as mouth ulcers or sores, vomiting, fever, chills, body aches, sore throat, muscle weakness, diarrhea, rash, loss of appetite, joint pain or swelling, yellow discoloration of skin and eyes, dark urine, breathing difficulty, dry cough, paleness, dizziness or fainting, unusual bruising or bleeding, seizures(fits), Consult a doctor. Do not stop using any medications without consulting a doctor.
Drug-Food Interactions
Drug-Food Interaction Summary:
- Caffeine: Limit excessive consumption of coffee, black tea, or caffeinated sodas, as high amounts of caffeine may reduce the effectiveness of this medicine in treating arthritis.
Drug-Food Interactions
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Reference
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