Side effects of vasodilator therapy

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Review

. 1988 Mar;11(3 Pt 2):II34-6.

doi: 10.1161/01.hyp.11.3_pt_2.ii34.

W A Pettinger 
¹
, H C Mitchell

Affiliations

Affiliation

• ¹ University of Texas Health Science Center, Department of Pharmacology, Dallas 75235.

• PMID:

  3280489

• DOI:

  10.1161/01.hyp.11.3_pt_2.ii34

Review

W A Pettinger et al.

Hypertension.

1988 Mar.

. 1988 Mar;11(3 Pt 2):II34-6.

doi: 10.1161/01.hyp.11.3_pt_2.ii34.

Authors

W A Pettinger 
¹
, H C Mitchell

Affiliation

• ¹ University of Texas Health Science Center, Department of Pharmacology, Dallas 75235.

• PMID:

  3280489

• DOI:

  10.1161/01.hyp.11.3_pt_2.ii34

Abstract

Vasodilating antihypertensive drugs have in common the capacity to activate the peripheral sympathetic nervous system through the carotid sinus baroreceptor reflex mechanism, thereby increasing heart rate, renin release, and sodium and water retention. They differ in their tendencies to augment cardiac output and to relieve or precipitate cardiac failure and arrhythmias. Vasodilating antihypertensive drugs can produce an array of side effects and toxicity including headache, facial changes, hair growth, varying degrees of sodium and water retention, and rarely systemic lupus erythematosus and allergic reactions. Detailed knowledge of these effects is a prerequisite to skillful individualization of antihypertensive regimens.

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Types, Side Effects & Precautions

This class of drugs is often used to treat cardiovascular conditions, such as hypertension.

Vasodilators are a group of medicines that dilate (open) blood vessels, which allows blood to flow more easily.

They’re used to treat or prevent:

• High blood pressure (hypertension)
• Heart failure
• Preeclampsia (high blood pressure during pregnancy)
• Angina (chest pain caused by reduced blood flow to the heart)
• Pulmonary hypertension (high blood pressure that affects the arteries in your lungs)

Vasodilators are often combined with other drugs and are rarely used alone.

Types of Vasodilators

There are different types of vasodilators, including:

• Arterial dilators (mainly affect the arteries)
• Venous dilators (mainly affect the veins)
• Mixed dilators (affect veins and arteries)

Arterial dilators are typically prescribed to treat high blood pressure and heart failure, while venous dilators are effective for angina and heart failure.

Your doctor will decide which vasodilator is right for you.

Common Vasodilators

The following are commonly prescribed vasodilators:

• Hydralazine
• ACE inhibitors
• Minoxidil

Side Effects of Vasodilators

Side Effects of vasodilators may include:

• Chest pain
• Heart palpitations (fluttering or pounding heartbeat)
• Rapid heartbeat
• Fluid retention
• Nausea or vomiting
• Dizziness
• Headache
• Flushing
• Excessive hair growth
• Nasal congestion

Vasodilator Precautions

Tell your doctor about any other medical conditions you have before starting on a vasodilator.

Vasodilators may help control your high blood pressure, but they won’t cure the condition.

Your doctor may suggest that you follow a special diet while taking vasodilators. Follow these instructions carefully.

Vasodilators can cause dizziness. Don’t drive or perform activities that require alertness until you know how these medicines affect you.

Tell your healthcare provider that you’re taking a vasodilator before having any type of medical procedure, including dental procedures.

Your doctor will want to perform frequent tests to monitor your body’s response to these medicines. Keep all appointments with your doctor’s office and laboratory.

Let your doctor know about all prescription, non-prescription, illegal, recreational, herbal, nutritional, or dietary drugs you’re taking before starting on a vasodilator.

Vasodilators and Alcohol

Alcohol may interfere with how vasodilators work in your body.

Avoid drinking alcohol while taking these medicines.

Vasodilators and Pregnancy

Tell your doctor if you’re pregnant or might become pregnant while taking a vasodilator.

Some of these medicines can cause unwanted effects in unborn babies.

You’ll have to discuss the risks and benefits of taking vasodilators during pregnancy.

Also, talk to your healthcare provider before taking a vasodilator if you’re breastfeeding.

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list of vasodilators, mechanism of action, restrictions and side effects

Contents

• 1 Vasodilators: list of drugs, action, contraindications and side effects
  • 1.1 Vasodilators: list, mechanism of action, restrictions and side effects
  • 1.2 What are vasodilators drugs?
  • 1.3 How do vasodilators work?
  • 1.4 Which drugs belong to the class of vasodilators?
  • 1.5 Nitrates and nitrites: popular vasodilators
  • 1.6 Calcium blockers: powerful vasodilators
  • 1.7 Adrenoceptor antagonists: blood pressure lowering agents
  • 1.8 Angiotensin converting enzyme inhibitors: drugs to improve corona ary blood flow
  • 1.9 Limitations and side effects effects of vasodilators
  • 1.10 How to take vasodilators correctly?
  • 1.11 Who should not take vasodilators?
  • 1.12 Do I need a prescription to get vasodilators?
  • 1. 13 Related videos:

List of vasodilators: mechanism of action, contraindications and side effects. Find out which vasodilators can help with hypertension, migraines and other circulatory disorders.

Vasodilators are medicines that increase the diameter of blood vessels, thereby increasing blood flow and improving the nutrition of organs and tissues. They can be used to treat a number of conditions associated with vasoconstriction, such as hypertension, angina, and ischemic stroke.

Many vasodilators work by relaxing the smooth muscles in the vascular walls. Some other drugs act on adrenoreceptors and reduce the level of stress hormones in the body. However, such drugs may have limitations and side effects that must be taken into account when prescribing.

Among the most well-known vasodilators are nitroglycerin, zinccardine, diltiazem, aminophylline, amiodarone, and many others. Each of them has its own unique characteristics in terms of mechanism of action, dosage and frequency of administration. Therefore, before using it is necessary to consult a doctor.

In general, vasodilators not only improve the quality of life of patients, but also promote rapid recovery from many diseases. The main thing is to choose the right drug and follow all the doctor’s recommendations.

Vasodilator drugs: list, mechanism of action, restrictions and side effects

Vasodilator drugs are medicines that help expand blood vessels and improve blood flow to organs and tissues. They are divided into several types, depending on the way they act on the vessels.

• Nitrate is one of the most common vasodilators used for angina pectoris. They work by dilating veins and arteries, reducing resistance in blood vessels and improving blood flow. Some of the more popular examples of nitrates include nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate.
• Calcium Antagonists – Often used to treat hypertension and sore throats, these drugs help widen arteries and lower blood pressure. Examples of calcium-containing antagonists include amlodipine and nifedipine.
• Alpha-blockers – These drugs help relax the muscles in the walls of blood vessels, which leads to vasodilation and increased blood flow. Examples of alpha blockers include doxazosin and prosazin.

Like any drug, vasodilators have their limitations and side effects. Some of the more common side effects include dizziness, nausea, drowsiness, and loss of strength. Some drugs can cause serious side effects such as low blood pressure and respiratory arrest. These medicines are not recommended for use by pregnant women, people with cardiovascular disease, or those taking other medicines as there is a risk of interaction.

What are vasodilators?

Vasodilators (vasodilators) are a group of medicines that can dilate blood vessels.

Vasodilator drugs are used to treat various conditions such as hypertension, tonsillitis, cardiac ischemia, gastrointestinal diseases, etc. They can also be prescribed for cerebral hemorrhages and cerebrovascular accidents.

But don’t forget that vasodilators are not safe and can have serious side effects. Therefore, their use should be carried out under the supervision of a physician and only on the basis of special medical indications.

How do vasodilators work?

Vasodilators have the ability to dilate blood vessels. This allows you to increase blood flow to certain organs and tissues. They act on smooth muscles in the walls of blood vessels, causing them to relax. The result is accelerated blood flow and lower blood pressure levels.

The mechanism of action of vasodilators depends on their type. Some dilate blood vessels, increasing the content of nitric oxide in the blood, while others work to reduce vasospasm by blocking calcium ions. Sometimes drugs are combined to increase the effectiveness of the action.

Despite potential risks, vasodilators are effective treatments for a variety of conditions such as hypertension, angina, and headache. Their use should be carried out only under the supervision of a physician and in accordance with the instructions on the packaging of the drug.

Which drugs belong to the class of vasodilators?

The class of vasodilators includes a variety of drugs that can dilate blood vessels. Depending on the mode of action and chemical composition, several subclasses of vasodilators are considered:

• Nitrates and nitrites;
• Calcium blockers;
• Beta blockers;
• ACE inhibitors;
• ARB preparations;
• Other vasodilators.

Nitrates and nitrites are a group of drugs that are widely used to treat angina and other cardiovascular conditions. Calcium blockers reduce calcium levels in vascular smooth muscle, blocking spasm. Beta-blockers work by slowing down the heart rate by regulating the work of the heart.

ACE inhibitors and ARBs are a group of vasodilators that help lower blood pressure. These medicines block the action of angiotensin, a hormone that raises blood pressure. Other vasodilators may include magnesium glucinate, S-adenosylmethionine, pentoxifylline, and others.

When choosing a vasodilator, the physician must consider the indications and contraindications for each individual case, as well as the limitations and side effects that may occur.

Nitrates and nitrites: popular vasodilators

Nitrates and nitrites are a group of vasodilators that are widely used in the treatment of cardiovascular diseases. These drugs promote vasodilation, improve blood circulation and reduce the load on the heart.

However, nitrates and nitrites may have some limitations and side effects. For example, with frequent use of these drugs, tolerance may develop, resulting in the need to increase the dose. Also, when using these drugs, headache, nausea, dizziness and other unpleasant symptoms may occur.

Before taking nitrates and nitrites, you should consult your doctor to evaluate the indications and risks associated with the use of these drugs. Also, you must follow the instructions for use and do not exceed the recommended doses.

Calcium blockers: powerful vasodilators

Calcium blockers are a class of drugs that block calcium channels in muscle cells in the walls of blood vessels. This leads to a decrease in the level of calcium in the cells, as well as to a decrease in the contraction of the muscle fibers of the vessel walls.

Calcium blockers can both dilate arteries and veins, which improves blood circulation in the body. In addition, they help lower blood pressure and relieve stress on the heart.

Calcium blockers may be prescribed by a physician for the treatment of hypertension, angina pectoris, arrhythmia and other conditions. However, the use of these drugs may be accompanied by side effects such as dizziness, swelling, fatigue, allergic reactions, and others.

When taking calcium blockers, a number of restrictions must be observed, in particular, to stop drinking alcohol, reduce the amount of salt in the diet and control the level of calcium in the blood.

• Examples of calcium blockers:
• Amlodipine
• Felodipine
• Lercanidipine
• Nifedipine

Prescription of calcium blockers should be done only by a doctor and taking into account the severity diseases, patient conditions and other factors.

Adrenoreceptor antagonists: blood pressure lowering agents

Adrenoceptor antagonists (AARs) are a type of vasodilator. They act on adrenoreceptors associated with the sympathetic nervous system and block their activity. This reduces the effect of adrenaline and norepinephrine on the heart and blood vessels, which has a positive effect on blood pressure.

AAPs are used to treat hypertension and other cardiovascular diseases. They are able to reduce systolic and diastolic pressure, as well as reduce the load on the heart.

The most common AARs include beta-blockers, which block beta-adrenergic receptors, and alpha-blockers, which block alpha-adrenergic receptors. In addition, there are combined preparations containing both beta and alpha blockers.

Most AARs have certain limitations and side effects associated with the effect on the sympathetic nervous system. They can cause dizziness, drowsiness, bradycardia, bronchospasm, increased blood triglycerides, etc. Therefore, they should be used only after prescription by a doctor and under his supervision.

Despite the possibility of unwanted side effects, AAPs are considered important and effective in lowering blood pressure and improving the quality of life of patients with hypertension and other cardiovascular diseases.

Angiotensin converting enzyme inhibitors: drugs to improve coronary blood flow

Angiotensin converting enzyme inhibitors (ACE inhibitors) are a class of drugs that are used to improve coronary blood flow. These drugs block the angiotensin-converting enzyme (ACE), which converts angiotensin I to angiotensin II. Angiotensin II contributes to vasoconstriction, which leads to a deterioration in blood flow and an increase in the workload on the heart.

The use of ACE inhibitors improves coronary blood flow by dilating blood vessels and relaxing the smooth muscles of the artery walls. This helps to reduce the load on the heart and improve its function.

ACE inhibitors are often used to treat hypertension, heart failure, coronary heart disease, diabetic nephropathy, and other diseases that are associated with impaired coronary blood flow.

• Restrictions : ACE inhibitors are not recommended during pregnancy or if there is an allergic reaction to the components of the drug.
• Side effects : Dizziness, nausea, diarrhea, cough, taste disturbances, angioedema and other rare adverse reactions may occur.

ACE inhibitors are effective vasodilators for improving coronary blood flow and treating a variety of conditions. However, before use, you should consult your doctor and familiarize yourself with the limitations and side effects.

Limitations and side effects of vasodilators

Although vasodilators may have a number of beneficial medical properties, they may also have undesirable side effects that must be considered in the selection and use of drugs. Common restrictions and side effects include:

• Headache: This symptom may be associated with various vasodilator drugs that can cause dilation of blood vessels in the brain.
• Tachycardia: Increased heart rate may be caused by vasodilator drugs, which relax the smooth muscles in the blood vessel wall.
• Hypotension: Vasodilator drugs can cause dangerous low blood pressure, especially when dosed incorrectly or combined with other drugs.

In addition, some vasodilators may have specific limitations and side effects that can lead to serious health problems for patients:

1. Nitroglycerin (Nitrospray): this drug may lower blood pressure, cause headache, nausea and vomiting, and cause redness of the skin due to dilation of blood vessels. Some patients may also experience an allergic reaction to the drug.
2. Vardenafil (Levitra): this drug is used to treat erectile dysfunction but may cause side effects such as visual and hearing problems, dizziness and nausea.
3. Alcohol: Although alcohol is not a drug, it can act as a vasodilator and cause unwanted side effects such as dizziness, nausea and weakness. It can also increase the side effects of many vasodilators.

In general, before using any vasodilator medication, a physician should be consulted to understand the limitations and side effects that the medication may cause and how to minimize health risks.

How to take vasodilators correctly?

Vasodilator drugs can be prescribed by a doctor in various doses and forms. Before you start taking, you must read the instructions for use of each specific drug. These instructions contain detailed information, including recommendations for dosage, frequency of administration and duration of the course.

It is important to follow your doctor’s instructions and instructions for use, even if you feel better. Do not stop taking medications on your own and change the dosage without consulting your doctor.

Vasodilators are usually given at certain times of the day and may be associated with meals. Some medications can cause side effects such as dizziness, upset stomach, and allergic reactions, so you should avoid drinking alcohol while taking it.

If you forget to take a dose of medicine, do not double the dose the next time. The missed dose should be taken as soon as possible or as directed by a physician.

In case of severe side effects or discomfort, you should immediately consult a doctor. Reception of vasodilators should be carried out under the supervision of a specialist.

Who should not take vasodilators?

Vasodilator drugs may be dangerous for some people and are contraindicated in the following cases:

• Allergy : If you have a known allergy to any of the ingredients in the drug, then this drug is strictly prohibited.
• Hypotension : Drugs that dilate the blood vessels may lower blood pressure. People diagnosed with hypotension should not take vasodilators.
• Pregnancy and breastfeeding : Placental protection during pregnancy prevents drugs from entering the baby’s circulation. However, some vasodilators can adversely affect fetal development. These drugs are also not recommended for use during breastfeeding.
• Heart problems : People with heart problems such as angina pectoris, arrhythmia, heart failure should only take vasodilators when prescribed by a doctor.
• Alcohol and other drugs : Some vasodilators should not be combined with alcohol and other drugs. Therefore, before you start taking any drug, you should consult your doctor about possible side effects and compatibility with other drugs and alcohol.

Do I need a prescription to get vasodilators?

Most vasodilators are prescription drugs because they can have serious effects on the body. Their appointment and dosage should be carried out only by a doctor on the basis of a patient examination and analysis of medical history.

However, there are some over-the-counter vasodilators available. These include, for example, nitroglycerin and isosorbide dinitrate, which are used in angina pectoris.

Keep in mind that all medications have side effects, and heart medications can cause serious complications, so you should see a doctor immediately if you experience symptoms.

Related videos:

Vasodilator drugs to reduce the symptoms of primary Raynaud’s syndrome

Relevance

Raynaud’s syndrome (phenomenon) is a condition in which small blood vessels in the extremities are affected, usually in the fingers, but also in the toes and other parts of the body. It occurs as a result of a temporary narrowing of the blood vessels, which leads to a change in skin color with accompanying numbness, tingling, and pain. Various triggers for this condition are known, such as stress, cold, and the use of vibrating hand tools. Conservative measures to control this condition include not smoking and keeping the extremities and environment warm. Medicines that dilate blood vessels, such as calcium channel blockers (CCBs), may be used, but they may have side effects. The purpose of this review is to investigate the efficacy and safety of blood vessel dilating drugs other than CCBs.

Description of studies and main results

For this update of the review, we found seven new studies, bringing the total number of studies to 15 (search up to 16 November 2020). This update now includes other routes of administration, such as intravenous (through the veins) and topical (cutaneous), as opposed to previous reviews that focused on oral forms of treatment. The studies were published between 1989 to 2013, a total of 635 participants were randomly assigned to a treatment group and a placebo control group. Many studies did not describe various aspects of research methods, such as randomization, allocation concealment, and blinding. The duration of treatment ranged from two weeks to six months.

Angiotensin converting enzyme (ACE) inhibitors as a class of drugs, namely enalapril and captopril in this review, generally increased the frequency of Raynaud’s syndrome attacks per week, but did not affect the severity of the attacks. Enalapril worsened subjective improvement, but captopril did not improve subjective outcomes and digital blood flow. Buflomedil showed a slight decrease in the frequency and severity of seizures along with an increase in side effects. Beraprost and dazoxibene did not show any change in either seizure frequency or severity or disability score, and their use was associated with an increase in side effects. Ketanserin did not show an improvement in the frequency or duration of seizures, in blood flow, assessed by digital methods, but showed an improvement in the Raynaud’s Syndrome Severity Scale. In a small study, moxisilite was shown to reduce the frequency and severity of seizures to a small extent, but along with an increase in side effects. Topical application of glyceryl trinitrate had no effect on reducing the frequency of attacks per week. One study reported subjective improvements in Raynaud’s Syndrome Score (RCS) scores. One small study reported improvements in the frequency and severity of seizures, measured subjectively. Headaches were the most significant and common side effect of treatment. Phosphodiesterase inhibitors did not reduce the frequency, severity, or duration of seizures and did not improve Raynaud’s syndrome score (RCS). One study reported that vardenafil alone reduced Raynaud’s Syndrome Score (RCS) scores, but this effect is likely small. One study reported that cilostazol increased the frequency and severity of seizures; further studies are needed to confirm this conclusion. The risk of headache as a side effect of treatment was increased with cilostazol. PF-00489 has been found to be791 at a dose of 20 mg slightly improved all subjective outcome measures and RCS scores.

Reliability of evidence

We have very low to moderate confidence in the results, so we cannot draw any definitive conclusions about the benefit of these drugs in reducing the symptoms of primary Raynaud’s syndrome. We cannot be certain due to the small number of participants included in the studies, problems with study design, and differences in the definition of treatment efficacy. Therefore, the clinical significance of these results is difficult to assess, especially when there is a high placebo response. It is also important that the results for each drug class, and for individual drugs within each class, must be interpreted in the context that they may have different pharmacological effects in addition to vasodilation. This must be taken into account when drawing any conclusions about the overall effects of each drug class and/or individual drug.