Gutron 5mg (Midodrine)

Gutron general information

What is Gutron used for?

Gutron tablets 5mg are used to treat primary neurogenic (originating from the nervous system) types of idiopathic (arising spontaneously or of unknown cause) orthostatic hypotension, when other medications do not provide adequate relief.  Orthostatic hypotension is a sudden fall in blood pressure when changing position, usually standing up from sitting or lying, also called postural hypotension.  These conditions include Bradbury-Eggleston and Shy-Drager (also known as multiple system atrophy) syndromes that are due to degeneration of nerve cells in a specific area of the brain and this impairs the involuntary autonomic functions like heart rate, blood pressure, bladder function and digestion.  Secondary orthostatic hypotension is also a symptom of other conditions, such as diabetes or nervous system disorders like Parkinson's disease and Gutron tablets 5mg are used in addition to other medications for these disorders.  Secondary orthostatic hypotension can also be due to low blood volume (hypovolaemia) from dehydration and some heart problems like bradycardia (low heart beat).  Orthostatic hypotension is caused by pooling of blood in the lower extremities, which happens when lying or sitting; on standing this slows down the return of blood to the heart and thereby reduces blood volume pumped out of the heart, which reduces the flow of blood to the brain and other parts of the body.  Normally, signals are sent by the autonomic nervous system from baroreceptors in the blood vessel walls, which detect changes in blood pressure.  This triggers the release of neurotransmitters like noradrenaline that counteract the effect of low blood pressure by stimulating increased heart rate, cardiac output and constriction of blood vessels, which increases blood pressure.  Gutron tablets 5mg are used to relieve symptoms of orthostatic hypotension including light headedness, dizziness, fainting, nausea, headache, blurred vision, numbness and tingling.   

How does Gutron work?

Gutron tablets 5mg contain midodrine the prodrug for desglymidodrine, which is a potent alpha agonist and vasopressor (increases blood pressure) that works by selective stimulation of the postsynaptic alpha adrenergic receptor and has little effect on the beta adrenergic receptors of the heart.  Alpha adrenergic receptors are found in many cells and are either alpha 1 or alpha 2.  Both receptors are involved in regulating neurotransmitters that bind to the alpha receptor, particularly adrenaline and noradrenaline, which in turn regulate the autonomic nervous system and are involved in the “fight or flight” response.  Alpha 1adrenergic receptors are found in smooth muscle of blood vessels.  Binding of an alpha agonist to these receptors stimulates contraction of smooth muscle and narrowing of the blood vessels (vasoconstriction).  Midodrine in Gutron tablets 5mg is converted to its active metabolite desglymidodrine that binds to alpha 1 adrenergic receptor and mimics the action of neurotransmitters like noradrenaline, which inactivates the formation of intracellular messages.  This action causes vasoconstriction increasing peripheral resistance, blood pressure and cardiac output to counteract the effects of postural hypotension and relieve symptoms like dizziness and lightheadness caused by reduced blood flow to the brain.  

What does Gutron contain?

Gutron tablets 5mg contain the active ingredient midodrine, the prodrug for the alpha agonist desglymidodrine, used to treat postural hypotension.  They also contain magnesium stearate, microcrystalline cellulose, purified talc, silicon dioxide, starch and sunset yellow FCF. 

Treating orthostatic hypotension with Gutron

Gutron tablets 5mg contain midodrine the prodrug for desglymidodrine, a potent alpha agonist and vasopressor (increases blood pressure) used to treat primary neurogenic (originating from the nervous system) types of idiopathic (arising spontaneously or of unknown cause) orthostatic hypotension, which is a sudden fall in blood pressure when changing position, when other medications due not provide adequate relief.  This condition is due to an impaired autonomic system, which controls involuntary functions like heart rate, blood pressure, bladder function and digestion and includes Bradbury-Eggleston and Shy-Drager (also known as multiple system atrophy) syndromes.  Secondary orthostatic hypotension is also a symptom of other conditions, such as diabetes, Parkinson's disease, low blood volume (hypovolaemia) due to dehydration and some heart problems like bradycardia (low heart beat).  Orthostatic hypotension is caused by pooling of blood in the lower extremities, which reduces cardiac output.  Normally, signals sent by the autonomic nervous system detect changes in blood pressure and trigger the release of neurotransmitters like noradrenaline that counteract the effect of low blood pressure by stimulating increased cardiac output, constriction of blood vessels and increased blood pressure.  Gutron tablets 5mg are used to relieve symptoms of orthostatic hypotension including light headedness, dizziness, fainting, nausea, headache, blurred vision, numbness and tingling. 

What are the side effects of Gutron?

The most commonly reported side effects when taking Gutron tablets 5mg include: dysuria (pain or difficulty urinating), urinary retention, piloerection (goosebumps), pruritus (itching),chills, flushing, skin rash, nausea, heartburn, stomatitis (inflammation of the mouth), paraesthesia (tingling and numbness), supine hypertension (continued high blood pressure when upright), bradycardia (slow heartbeat), sleep disorder and insomnia, headache, restlessness, excitability, irritability.

When should Gutron not be used?

You should not use Gutron tablets 5mg if you:

• are allergic to midodrine or any ingredients in Gutron
• are pregnant or are breastfeeding, without discussion with your doctor
• have renal insufficiency or acute kidney disease
• have hyperthyroidism (overactive thyroid)
• have heart disease or hypertension (high blood pressure)
• have narrow-angle glaucoma
• have pheochromocytoma, a tumour of the adrenal glands
• have obliterative or spastic vessel disease when blood vessels contract and narrow when cold or emotional
• have hypertrophy (overgrowth) of the prostate gland with formation of residual urine, urinary retention
• are taking medicines that interact with Gutron, including digoxin, other alpha agonists like the decongestant phenylephrine, the vasopressor methoxamine, tricyclic antidepressants, antihistamines, thyroid hormones, MAO inhibitors, dihydroergotamine for migraine, salt-retaining steroids like fludrocortisone, α-adrenergic blockers like prazosine for hypertension and the vasodilator phentolamine, the antipsychotic reserpine, the anticholinergic atropine, corticosteroid.

What medications interact with Gutron?

Several medications interact with Gutron tablets 5mg and should either not be taken while you are taking Gutron or only after discussion and instruction from your doctor:

• Drugs that cause a serious reaction with Gutron: digoxin, salt-retaining steroids like fludrocortisone, α-adrenergic blockers like prazosine for hypertension and the vasodilator phentolamine
• Drugs that affect Gutron: other alpha agonists like the decongestant phenylephrine, the vasopressor methoxamine, tricyclic antidepressants, antihistamines, thyroid hormones, MAO inhibitors, dihydroergotamine for migraine, the antipsychotic reserpine
• Drugs that are affected by Gutron: the anticholinergic atropine, corticosteroid

How should Gutron be taken?

You should take your Gutron tablets 5mg swallowed whole with a glass of water 3 times daily, but take the last dose before your evening meal.  Your dose may be increased and your blood pressure will be monitored when you begin taking your Gutron tablets 5mg.  You should continue to take your Gutron tablets 5mg for as long as recommended by your doctor, which will depend on how well you respond and your blood pressure measurements.

How long should you take Gutron?

You should continue to take your Gutron tablets 5mg for as long as recommended by your doctor, which will depend on how well you respond and your blood pressure measurements.

Missed dose of Gutron

If you miss a dose of Gutron tablets 5mg take it as soon as you remember, unless it is time to take the next dose, then skip the missed dose.  Do not take a double dose.

How should Gutron be stored?

You should store your Gutron below 25°C in a cool dry place.