Metoprolol (Lopressor / Toprol XL)

Metoprolol (Lopressor / Toprol XL)

What is Metoprolol (Lopressor)?

Metoprolol is the generic form of the drug Lopressor which is also marketed as Toprol XL. It is a prescription medicine that is used to treat high blood pressure (hypertension), as it aids in lowering the blood pressure and helps in preventing heart attacks, strokes and kidney problems. It is also used to prevent and treat chest pain (angina) and improves chances of survival after a heart attack. In some cases, it can also be used to treat an irregular heartbeat.

Metoprolol is a beta blocker. These are medications that work by blocking the effects of the hormone adrenaline, also known as epinephrine. These drugs relax the blood vessels and slow down the heart rate, which in turn improves the blood flow and lowers blood pressure.

Metoprolol is sometimes prescribed as a long-term treatment for heart failure, this form of the drug is known as Toprol XL. However, it can be used as a long or short-term treatment.

It is sometimes used in conjunction with other medication, using it as part of a combination therapy, alongside chlorthalidone or hydrochlorothiazide.  It can also be used to treat conditions aside from heart issues, such as movement disorders which are caused by drugs used to treat mental illnesses, and can also help in treating migraine headaches.

In 1978, metoprolol was approved under the brand name of Lopressor. It is widely used today as an effective prescription drug by doctors worldwide. It is normally taken orally in the form of a hard and coated pill.  

What are the warnings for taking Metoprolol (Lopressor)?

Metoprolol is a treatment and not a cure for the conditions it is used to treat. It may take a few weeks until you can start to notice the benefits of the medication. Certain allergies may worsen the reactions to the drug, this can include being unresponsive to epinephrine. If you have asthma, heart failure (in some cases) or a slow heart rate, beta blocker medication is not recommended.

Doctors normally do not prescribe the drug to those who suffer from diabetes or people older than 65. 

However, it is often dependent on the health of the person. It is always best to consult with a doctor should you have any of these conditions.

Metoprolol warnings include:

  • Surgery: You should let your doctor know if you are expecting to have surgery done, this also includes dental surgery.
  • Asthma or chronic obstructive pulmonary disease (COPD): It is best not to take metoprolol if you are asthmatic or have other breathing related issues. This is due to the fact that metoprolol is able to block receptors in the breathing passages, narrowing them and worsening any breathing problems you may have.
  • Diabetes: Metoprolol can eliminate tremors and increase your heart rate, which are both indications of low blood sugar. If these signals are not present, it can be harder to recognise the signs of low blood sugar, thus making it dangerous for people with diabetes to take the drug.
  • Poor blood circulation: Having bad circulation in your hands and feet can be worsened by taking metoprolol as the drug decreases blood pressure, resulting in less blood flow to these areas.
  • Breast feeding: Metoprolol can enter your breast milk and be passed to your baby when breastfeeding, it can be dangerous to the health of the baby.
  • Pregnancy: With metoprolol being a category C drug, it means that research conducted on animals has shown negative effects on the foetus when the mother is taking the drug. In addition, it means that there haven’t been enough studies conducted on humans to draw conclusive findings on how this drug will affect your unborn child.
  • Seniors: Seniors are often given a smaller dose of metoprolol first, with it then increasing gradually.
  • Children and teenagers: Children between the ages of one and 17 are able to be given the immediate-release form of metoprolol.

What are the side effects for Metoprolol (Lopressor / Toprol XL)?

There are a number of side effects associated with the drug, it is best to speak to your doctor about the possible side effects and consult with him/her should any of these persist and become bothersome. Some of the less severe and more common effects include:

  • Tiredness: Metoprolol will slow your heart rate down through blocking the hormone adrenaline. This results in blood being transported to the brain at a slower pace, making you feel tired. This can go away after a few days of first taking the drug as the body adapts to its effects.
  • Diarrhoea / constipation: Metoprolol is able to block the nerve signals coming from the brain to the gut which can affect the digestive system in either speeding it up or slowing it down. If it moves faster it can result in diarrhoea, and in if it moves slower it results in constipation.
  • Light dizziness: By lowering your blood pressure, metoprolol can lead to feeling mildly dizzy, particularly when moving suddenly. This feeling will normally go away when the body has adjusted to the drug. However, severe drops in blood pressure may result in severe dizziness, which is considered a serious side effect. It is best to consult with a doctor should you be experiencing serious dizziness.
  • Breathing problems: Metoprolol tightens the airways by blocking the signals from the brain to muscles in the passages of the lungs (bronchioles), which allows the lungs to relax. This causes coughing, wheezing and shortness of breath.
  • Bradycardia (abnormally slow heart beat): Metoprolol is known to slow down the impulses of nerves travelling from the brain to the heart, which in turn can slow your heart rate to a very slow level.
  • Decreased libido: In men metoprolol can disrupt the section of the brain that signals an erection, it can also make it difficult to orgasm for women and men.
  • Rash: Skin rashes can start to develop because of metoprolol use. Hives and itching can also be experienced, this is considered more serious and it is important to seek professional advice from your doctor should you experience this symptom.

There are also a number of more serious side effects, should you experience any of these, it is advised that you consult with your doctor immediately. These can include:

  • Hypotension (low blood pressure): If the dose of metoprolol is too high, it can result in the blood dropping to severely low levels. This can also be a result of heart receptors being overly sensitive to the drug. Symptoms can include fainting, light-headedness and severe dizziness.
  • Cold feet and hands: Metoprolol, being a beta blocker and slowing down the heart rate and blood pressure, can cause less blood to be pumped to the feet and hands. This results in loss of warmth, making them cold, which can lead to them feeling painful.
  • Severe bradycardia (very slow heart rate): As mentioned, in being a beta blocker, metoprolol can slow down the nerve impulses to the heart, dropping the heart beat to a level so severe it can lead to the heart stopping.
  • Severe depression: It is not known as to whether metoprolol is the direct cause of depression, as people with heart diseases tend to be more at risk for developing depression, but this could be as a result of the condition rather than the medication itself. If you are already experiencing depression, the drug can worsen the effects of the condition.
  • Serious fatigue: Metoprolol slows down your heart rate and therefore decreases the blood flow to your arms, legs and brain, making you feel sluggish and sometimes exhausted. Some people experience fatigue that worsens with each day, making it difficult to function normally.

Can Metoprolol (Lopressor / Toprol XL) interfere with other medications?

It is possible for metoprolol to interact with other medications you may be taking, these also include vitamins and herbal drugs. It is best for your doctor to always be aware of what other medications you may be on in order for him/her to manage them carefully. It helps to have the same pharmacy fill out all of your prescriptions in order to ensure no drug interferences take place.

Some medications that can possibly interfere with metoprolol are:

  • Heart rhythm drugs
  • Mental health drugs
  • Calcium channel blockers
  • Alpha blockers

Metoprolol (Lopressor / Toprol XL) outlook

Being a prescription drug used for serious conditions, it is important to make sure that you always consult with your doctor before taking the drug as well as if you develop any severe or persisting side effects.

It is important to take the drug orally, on schedule and as prescribed.

Disclaimer - is for informational purposes only. It is not intended to diagnose or treat any condition or illness or act as a substitute for professional medical advice.