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Generic Name:metoprolol

Other Brand Names: Lopressor


  Table of Contents
  • Overview
  • Side Effects and Interactions
  • Taking the Medicine
  • Special Precautions
  •   Side Effects and Interactions

    Lopressor or Toprol can cause a number of side effects. These include slow heart rate, cold hands and feet, insomnia, nightmares, blurred vision, sexual difficulties, nerve tingling, dizziness, nausea, stomach ache, gas, diarrhea, indigestion, rash, arthritis and muscle pain.

    The medicine may also have a negative effect on cholesterol and other blood fats, so a lipid test before treatment and periodically thereafter would be prudent.

    Lopressor or Toprol are a little more likely to affect the nervous system than certain other drugs in this class.

    Be alert for the beta blocker blues. Symptoms of psychological depression, fatigue, decreased concentration, memory loss and mood swings may come on slowly and insidiously.

    Notify your physician promptly of any adverse reactions, especially breathing difficulties, fluid retention in the legs or a night cough.

    Never stop taking any beta blocker medication abruptly unless you are under very close medical supervision. Angina or a heart attack could occur.

    These drugs may also make treatment of diabetes and thyroid disorders more complicated. Your physician will need to monitor such conditions closely.

    Lopressor or Toprol can interact with a number of other medicines. Antacids containing aluminum or calcium can reduce absorption and interfere with the effectiveness of Lopressor or Toprol, as can many arthritis drugs and aspirin.

    Cholesterol-lowering medications like Cholybar, Questran or Colestid and penicillin-type antibiotics might have the same effect on this beta blocker.

    The ulcer medicines Tagamet and Zantac may increase the effects of either Lopressor or Toprol, however.

    Other blood pressure medicines such as Apresoline or calcium channel blockers like Calan or Procardia could interact with either Lopressor or Toprol so that the blood-pressure lowering power of each drug is enhanced.

    Minipress is more likely to cause fainting problems when combined with Lopressor.

    Be aware that over-the-counter asthma medicines containing epinephrine, the blood thinner Coumadin or ergotamine-containing migraine drugs like Cafergot could all interact badly with this drug.

    Check with your doctor and pharmacist before taking any other drugs to make sure you are aware of the risks the combination may carry.