Isoxsuprine 40 mg (SR) is an oral medicine belonging to the category of vasodilators and is used for the following indications: 

1. Improve blood flow to the brain.  
2. Relax the uterus and delay premature labor.  
3. Numbness of fingers (Raynaud’s syndrome)  
4. Improve blood flow to arteries. (Buerger’s disease) 

More Common  

1. Dizziness or lightheadedness, especially when standing up quickly  
2. Flushing or warmth in the face  
3. Headache  
4. Nausea or upset stomach  
5. Fast heartbeat (palpitations)  
6. Sweating  
7. Tremors or nervousness  
8. Low blood pressure (hypotension) 

Less Common 

1. Chest pain or tightness  
2. Shortness of breath 
3. Skin rash or itching 
4. Swelling of hands, feet, or ankles 
5. Blurred vision 
6. Fainting or severe drop in blood pressure 
7. Irregular heartbeat 
8. Muscle cramps or weakness 

Isoxsuprine works by activating beta-adrenergic receptors, which relax the smooth muscles in blood vessels and the uterus. This widening of blood vessels improves circulation, while uterine relaxation helps delay early labor.

Pregnancy

Isoxsuprine may be used during pregnancy to help relax the uterus and delay early labor. It works by calming the muscles, giving the baby more time to grow before birth. 

Breastfeeding

 If you’re breastfeeding, small amounts may pass into your milk, which is usually safe, but high doses might lower milk supply, so always check with your doctor.

Liver and Kidney Problems

 If you have kidney or liver issues, isoxsuprine may cause stronger side effects like dizziness. Let your doctor know so they can adjust the dose if needed.

Avoid consuming alcohol and smoking simultaneously, as it may affect the drug’s action and show effects like falling blood pressure, leading to severe drowsiness, sedation, and coma in severe cases.

Avoid taking Isoxsuprine 40 mg (SR) with the following medicines, as it may increase or decrease the desired effect, or in worse cases, it could be fatal:

IUPAC (International Union of Pure and Applied Chemistry)/ Chemical name

4-{1-Hydroxy-2-[(1-methyl-2-phenoxyethyl) amino] propyl} phenol.

Daily dose

 Take Isoxsuprine exactly as your doctor recommends. The dose may change based on your condition and how well you respond. Do not take more than prescribed without consulting your doctor.

Missed Dose

 If you forget to take your medicine, take the medication as soon as you remember. If it’s nearly time for your next dose, skip the missed one and continue with your regular schedule. Always consult the doctor before making any changes to your dosage.

Overdose

It is not recommended to take more than 80 mg of Isoxsuprine per day, as it may cause severe overdosing effects like extreme drowsiness, confusion, unconsciousness, sweating, double vision, low blood pressure, and slurred speech. Immediately seek medical attention and meet the doctor if necessary.

1. Store the medicine at room temperature 
2. Keep away from sunlight and moisture 
3. Keep out of reach of children 

1. Take Isoxsuprine exactly as prescribed by your doctor, at the same time each day. 
2. Do not stop taking Isoxsuprine without your doctor’s approval, even if you feel better. 
3. If you forget to take Isoxsuprine, take it as soon as you remember. If it’s almost time for your next dose, skip the missed dose. 

Isoxsuprine helps improve blood flow by relaxing blood vessels, making it easier for blood to reach your brain, hands, and feet. It’s often used for cold fingers (like in Raynaud’s), poor circulation, or blocked arteries. Sometimes, doctors also use it to help calm the uterus and delay early labor. You might feel dizzy or flushed or get a headache or nausea. Taking it with food can help your stomach but avoid alcohol, as it can make dizziness worse. Store it in a cool, dry place. Isoxsuprine overdose occurs after the 80 mg threshold; it causes hypotension and tachycardia. Pregnant women, the elderly, and those with heart disease should consult doctor before consuming this medication.

What are the uses of Isoxsuprine tablets?

Isoxsuprine tablets are used to improve blood flow in conditions like peripheral artery disease and Raynaud’s, helping relieve leg cramps or cold fingers. They’re also sometimes used during pregnancy to relax the uterus and delay early labor.

What are the side effects of Isoxsuprine tablets?

Isoxsuprine may cause dizziness, flushing, headache, fast heartbeat, or nausea. Rarely, it can lead to low blood pressure or allergic reactions like rash or swelling.

What is the mechanism of action of Isoxsuprine? 

The usual maximum dose of isoxsuprine is around 80 to 120 mg per day, divided into multiple doses. An overdose may occur above this range, especially if taken all at once, but exact toxic thresholds are not well defined.

What is the highest dose of Isoxsuprine?

Isoxsuprine belongs to the vasodilator drug class, which means it helps widen blood vessels to improve blood flow. It also acts as a beta-adrenergic agonist, relaxing smooth muscles in blood vessels and the uterus.

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