What are some Atenolol side effects


This is how atenolol works

Atenolol is a water-soluble active ingredient that only binds to a certain type (beta-1) of beta receptors. It is therefore also called a beta-1 receptor blocker. Atenolol attacks the autonomic nervous system, which controls blood pressure and the work of the heart, among other things. Certain messenger substances (neurotransmitters) such as adrenaline, noradrenaline and dopamine regulate these processes. The neurotransmitter adrenaline, for example, binds to the beta receptors of the heart muscle and thus increases its beat rate, which is why blood pressure rises.

Due to its similar molecular structure, atenolol can dock to the binding sites for neurotransmitters and block them for adrenaline, so that the effect of the body's own hormone is weakened. This lowers blood pressure. Since the excitability of the heart muscle also decreases, the tendency to certain types of cardiac arrhythmias decreases at the same time.

Atenolol uptake, breakdown and excretion

After ingestion through the mouth (orally), only half of the active ingredient atenolol is absorbed from the intestine into the blood. There it is converted to a very small extent into intermediate products which, however, have no medicinal effect. After that, the breakdown takes place mainly via the kidneys. The breakdown products are finally excreted in the urine.

When is Atenolol used?

Atenolol is used to treat irregular heartbeat (such as atrial fibrillation), high blood pressure, and to prevent ventricular fibrillation. Ventricular fibrillation is a life-threatening disorder of the heart, in which hardly any blood is pumped into the body.

This is how atenolol is used

Atenolol is available as a tablet with different active ingredient concentrations (25mg, 50mg and 100mg). For many cardiovascular complaints, one tablet with 25 mg of active ingredient once a day is sufficient. In the case of high blood pressure, 50 mg atenolol per day are prescribed at the beginning of therapy. If necessary, the dosage can be increased to 100 mg of active ingredient per day for a week. The dosage prescribed by the doctor must be strictly followed.

What side effects does atenolol have?

Common atenolol side effects affect the cardiovascular system. An unusually slow heartbeat (bradycardia) can occur, especially at the beginning of treatment, and blood pressure can drop more than desired. Many patients also feel cold in their hands and feet. Dizziness or profuse sweating are possible, especially at the beginning of treatment with the active ingredient. In addition, gastrointestinal complaints such as nausea, vomiting, diarrhea or constipation of the stool often occur during therapy with atenolol.

Side effects that are seen uncommonly (in less than one percent of patients) include inflammation of the conjunctiva of the eye (conjunctivitis), muscle cramps, difficulty sleeping and an increase in blood sugar levels.

Atenolol rarely triggers side effects such as circulatory disorders or cramps in the arteries of the fingers. Reddening of the skin, bleeding in the subcutaneous tissue (purpura), breathing difficulties and visual disturbances are also possible. Hallucinations, psychoses, confusion, headaches and nightmares occur very rarely.

If you experience side effects or symptoms not mentioned here in connection with the use of medication, please always consult your doctor.

When should I not take Atenolol?

Atenolol should not be taken

  • if you are hypersensitive (allergic) to the active ingredient or other beta-blockers
  • in sinus node syndrome
  • if the pH of the blood is too acidic (acidosis)
  • if antidepressants are taken at the same time (e.g. MAO inhibitors)


Medicines taken at the same time, such as water tablets (diuretics), antidepressants or certain anesthetics (barbiturates), increase the blood pressure-lowering effect of atenolol. On the other hand, if the blood pressure medication is stopped while atenolol is being used, blood pressure can rise dangerously.

Insulin increases the blood sugar lowering effect of beta blockers, which can cause the blood sugar level to be too low (hypoglycaemia). At the same time, however, typical symptoms of hypoglycaemia such as an accelerated heartbeat are masked by atenolol. As a diabetic who needs insulin, you should therefore regularly check your blood sugar levels. carry out.

pregnancy and breast feeding period

During pregnancy, expectant mothers should avoid atenolol for the first three months. The active ingredient crosses the placenta and can be transferred to the fetus. No studies on possible effects on the embryo are available for this period. Damage to the unborn child cannot be ruled out.

During the last three months of pregnancy, growth retardation and slightly increased blood pressure were observed in the fetus. Therefore, you should only take the drug at this stage under the supervision of a doctor. Atenolol should not be used shortly before birth (24 to 48 hours beforehand), as there is a risk of developing bardycardia or shortness of breath in the newborn.

The active ingredient can be found in breast milk and passed on to the child when breastfeeding. Although the amount of active substance ingested with breast milk is likely to be safe for the infant, the condition of the child should be monitored by a doctor.

Driving and using machines

Atenolol can impair the ability to react even with the correct dosage. Safe use of machines and the ability to actively participate in road traffic can therefore be restricted, especially at the beginning of therapy.

This is how they get medication with atenolol

Atenolol is available in the pharmacy against a prescription as a tablet with various active ingredient concentrations.

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