Medically reviewed by Jessica Swirble, PharmD
Last updated on 7/2/2024

Drug Information | Side Effects | Use & Dosage | Request a Prescription

The use of metoprolol ER can lead to various side effects in some individuals.

Common mild side effects of metoprolol ER use include:

• Fatigue or tiredness
  
• Dizziness or lightheadedness
  
• Nausea or upset stomach
  
• Vomiting
  
• Diarrhea or constipation
  
• Slow heart rate (bradycardia)
  
• Cold hands and feet
  
• Shortness of breath
  
• Trouble sleeping (insomnia)
  
  

More severe side effects of metoprolol ER use can include:

• Very slow heartbeat
  
• Very low blood pressure
  
• Change in heart rhythm
  
• Severe allergic reactions (such as rash, itching, swelling of the face, tongue, or throat, trouble breathing)
  
• Chest pain or tightness
  
• Swelling of the ankles or feet (edema)
  
• Fainting or severe dizziness
  
• Blue color to your fingers or toes
  
• Severe headache
  
• Unusual sweating
  
• New or worsening symptoms of heart failure (such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain)
  
  

If you experience any severe or concerning side effects while taking Metoprolol ER, contact your healthcare provider right away.

Tell your healthcare provider about any existing medical conditions, allergies, or other medications you are taking before starting treatment with metoprolol ER. This includes prescription drugs, over-the-counter medications, and dietary supplements, as they may interact with metoprolol ER.

Tell your provider if you are taking these medications or supplements:

• Other blood pressure medications
  
• Medications that slow the heart rate
  
• Medications that affect heart rhythm
  
• Nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen and aspirin)
  
• Antidepressants or anti-anxiety medications
  
• Any drugs or supplements that may affect heart rate or blood pressure
  
  

You should also mention medical conditions such as:

• Asthma or other breathing disorders
  
• Diabetes (Metoprolol ER may mask signs of low blood sugar)
  
• Thyroid disorders
  
• Kidney or liver disease
  
• A history of severe allergic reactions
  
  

If you are pregnant, planning to become pregnant, or breastfeeding, consult your healthcare provider before using metoprolol ER to assess potential risks and benefits.

Take metoprolol ER exactly as prescribed by your healthcare provider. Do not exceed the recommended dose or duration of treatment.

Metoprolol ER should be taken with a meal or just after eating to improve absorption and reduce the risk of stomach upset. Follow your healthcare provider's instructions for optimal effectiveness.

Avoid alcohol and activities that require alertness until you understand how Metoprolol ER affects you, as it can cause dizziness and fatigue.

Store metoprolol ER at room temperature, away from moisture and heat. Keep it out of reach of children.

In case of a metoprolol ER overdose, seek medical attention immediately. Symptoms of overdose may include severe dizziness, fainting, difficulty breathing, or an unusually slow or irregular heartbeat. If you suspect an overdose, contact the poison control helpline at 1-800-222-1222 or call emergency services.