Medications helping fainting

7th March 2023 | Dr Boon Lim

Introduction

Vasovagal syncope and orthostatic intolerance can significantly impact daily life, causing symptoms such as dizziness, lightheadedness, and fainting. Medications play a crucial role in the management of these conditions by improving blood pressure regulation and enhancing overall cardiovascular stability. This article focuses on three commonly prescribed medications—midodrine, fludrocortisone, and salt tablets—and their benefits in relieving symptoms associated with vasovagal syncope and orthostatic intolerance.

Midodrine

Midodrine is an alpha-adrenergic agonist that helps constrict blood vessels, thereby increasing peripheral resistance and improving blood pressure regulation. Here are key considerations:

– Mechanism of Action: Midodrine stimulates alpha-adrenergic receptors in blood vessels, causing vasoconstriction and elevating blood pressure.

– Benefits: By improving blood pressure control, midodrine can help alleviate symptoms of orthostatic hypotension (low blood pressure upon standing) such as dizziness, lightheadedness, and the risk of fainting.

– Usage and Dosage: Midodrine is typically taken orally, and the dosage is determined by a healthcare professional based on individual needs. It is often taken 2-3 times daily, with the last dose taken several hours before bedtime to prevent supine hypertension (high blood pressure while lying down).

Ivabradine

Ivabradine is a selective sinus node blocker, by working on a very highly specialiased group of cells in your natural pacemaker (located in the right atrium of the heart) which determines heart rate. Here are key considerations:

– Mechanism of Action: Ivabradine is a “funny” current blocker, which blocks the flow of this current which stimulates activation of pacemaker cells. The effect of this is to slow down the heart rate. This drug does not typically reduce the Blood Pressure (which is something that beta blockers do) and so can be useful to reduce heart rates particularly when beta blockers are not tolerated.

– Benefits: By slowing the heart rate down, patients may feel less sensation of palpitations without lowering blood pressure.

– Usage and Dosage: Ivabradine is usually prescribed twice daily at the usual starting dose of 2.5mg twice daily, in the morning and evening. If there is a partial effect (ie palpitations improve but still present) the drug could be gradually uptitrated in 2.5mg dose increments until a dose of 7.5mg twice daily.

– Side Effects: Some patients develop “flashing lights” due to ivabradine. This may occur shortly after taking ivabradine, but doesn’t cause any long term effects. It typically does not affect your vision and will not cause any permanent issues, and are reversible if you stop ivabradine. Some patients are comfortable tolerating this side effect, but if you cannot continue taking this, then stop, and discuss this with your doctor. An alternative medication to reduce your palpitations is a beta blocker, which your doctor may consider. 

Beta Blockers

Beta Blockers are drugs which your doctor may prescribe if you have palpitations (typically high heart rates).

– Mechanism of Action: Beta blockers are a class of drugs which block the beta-adrenaline receptor, which blocks the effect of adrenaline on your heart and vascular system. The effect of this drug can be thought of as “calming drug” as it blocks the effect of your fight of flight response, mediated by the adrenaline system.

– Benefits: Beta blockers can be useful in reducing palpitations. By being “anti-adrenaline” in its effect, it can also create a sense of calmness. 

– Usage and Dosage: The dose depends on the beta blocker used. 

Commonly prescribed drugs include: 1) Propranolol 10mg twice daily,  and 2) bisoprolol 1.25mg or 2.5mg once daily.

The dose is determined by your doctor based on your individual needs. 

– Special considerations. Beta blockers and ivabradine are both drugs that may be considered by your doctor to help with symptoms of palpitations. How do you choose the ideal drug ? Our experience is that if you have a low blood pressure or low normal blood pressure and you have a tendency to palpitations whilst standing, then ivabradine may be a better starting choice for symptoms of palpitations, as this does not reduce your blood pressure further. 

Beta blockers are more suitable typically if you have an entirely normal or higher blood pressures, and you also suffer with palpitations. Beta blockers, may help by lowering your blood pressure, in addition to calming palpitations.

Fludrocortisone

Fludrocortisone is a mineralocorticoid that helps increase sodium reabsorption in the kidneys, promoting fluid retention and enhancing blood volume. Consider the following:

– Mechanism of Action: Fludrocortisone acts on the kidneys to increase the reabsorption of sodium and water, thereby expanding blood volume and improving blood pressure control.

– Benefits: By optimizing blood volume, fludrocortisone can help alleviate symptoms of orthostatic hypotension and improve overall cardiovascular stability.

– Usage and Dosage: Fludrocortisone is typically taken orally once daily. The dosage is determined by a healthcare professional based on individual needs, and it is important to monitor blood pressure and electrolyte levels regularly while on this medication.

Salt Tablets

Salt tablets or capsules contain concentrated amounts of sodium chloride and are used to supplement sodium levels in individuals with low blood pressure and sodium loss. Here are key considerations:

– Mechanism of Action: Salt tablets provide additional sodium, which helps increase blood volume and improve blood pressure regulation.

– Benefits: By supplementing sodium levels, salt tablets can help alleviate symptoms of orthostatic hypotension, particularly in individuals with sodium loss or low blood pressure.

– Usage and Dosage: The usage and dosage of salt tablets should be determined in consultation with a healthcare professional, who can guide individuals on the appropriate amount of sodium supplementation needed based on individual requirements.

Conclusion

Medications such as midodrine, fludrocortisone, and salt tablets play a valuable role in the management of vasovagal syncope and orthostatic intolerance. Midodrine helps improve blood pressure regulation through vasoconstriction, while fludrocortisone optimizes blood volume through sodium retention. Salt tablets provide supplemental sodium to support blood volume and blood pressure stability. It is important to note that medication usage should be determined and monitored by healthcare professionals, who can tailor treatment plans to individual needs. By incorporating these medications as part of a comprehensive treatment approach, individuals with vasovagal syncope and orthostatic intolerance can experience symptom relief, improved quality of life, and enhanced cardiovascular stability.

While midodrine, fludrocortisone, and salt tablets can be effective in managing symptoms of vasovagal syncope and orthostatic intolerance, they can also have potential side effects. It is important to be aware of these side effects and discuss them with a healthcare professional before starting any medication. Here are some common side effects associated with each medication:

Midodrine:

– Supine Hypertension: Midodrine can cause high blood pressure while lying down (supine hypertension). To minimize this risk, the last dose should be taken several hours before bedtime.

– Pilomotor reactions: Midodrine can cause pilomotor reactions, resulting in goosebumps and scalp tingling.

– Urinary Retention: Some individuals may experience difficulty in emptying the bladder, leading to urinary retention.

– Scalp and Skin Tingling: Midodrine may cause tingling sensations or a feeling of “pins and needles” on the scalp or skin.

Fludrocortisone:

– Fluid Retention and Edema: Fludrocortisone can lead to fluid retention, which may cause swelling (edema) in the legs, ankles, or other areas of the body.

– High Blood Pressure: Fludrocortisone can increase blood pressure, so regular monitoring is important.

– Electrolyte Imbalances: Fludrocortisone may affect electrolyte levels, particularly potassium. Regular monitoring of electrolyte levels is essential.

Salt Tablets:

– Fluid Retention and Edema: Increasing sodium intake through salt tablets can cause fluid retention and edema, especially in individuals who are prone to retaining fluids.

– Increased Blood Pressure: Higher sodium intake may contribute to elevated blood pressure, so monitoring blood pressure regularly is important.

– Electrolyte Imbalances: Sodium supplementation can impact electrolyte balance, so monitoring electrolyte levels is crucial.

It’s important to note that individual responses to medications can vary, and not everyone may experience these side effects. However, if any side effects are noticed while taking these medications, it is essential to inform a healthcare professional. They can provide guidance, monitor for potential complications, and make necessary adjustments to the treatment plan to ensure the best possible outcomes.

Remember, the benefits of these medications often outweigh the potential side effects, but close monitoring and regular communication with a healthcare professional are key to managing any medication regimen effectively.

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