Dicloxacillin: uses and side effects

Dicloxacillin is a beta-lactam antibiotic belonging to the penicillin group and resistant to penicillinases, which are enzymes that produce certain microorganisms, capable of hydrolyzing and inactivating penicillin.

It is used to treat infections caused by bacteria gram positive, for example Staphylococcus aureus, and to treat infections caused by group A streptococci such as Streptococcus pneumoniae.

In this article we tell you in which cases dicloxacillin is indicated and the possible side effects it can cause.

A little history

The first antibiotic that was widely used in medicine was penicillin G or benzylpenicillin, discovered by Alexander Fleming in 1928, for which he won a Nobel Prize. Since then, advances in science have allowed the development of new molecules for the specific treatment of the various infections caused by bacteria.

Currently, there are different groups of beta-lactams, in addition to penicillin G, such as ampicillin, amoxicillin or penicillinase-resistant penicillins, such as the dicloxacillin we are treating in this article.

In addition to penicillin G, there are other beta-lactam antibiotics such as ampicillin, amoxicillin or penicillinase-resistant penicillins, such as dicloxacillin.

Therapeutic indications of penicillins

Dicloxacillin is indicated in adults and children over 12 years old, in the treatment of the following bacterial infections:

  • Acute Streptococcal Pharyngotonsillitis
  • Skin infections and attached structures such as scarlet fever, impetigo or boils
  • Infections of dental and periodontal structures

The dosage and duration of treatment will be determined by the type of condition for which it is indicated.

Mechanism of action

The mechanism of action of penicillins it is associated with the activation of enzymes that alter the cell wall of bacteria acting as bactericides, that is, they destroy bacteria.

Some warnings and precautions for use

It is important that before starting treatment with dicloxacillin be notified if there has ever been an allergic reaction to penicillins or other beta-lactams. Like the vast majority of antibiotics, dIloxacillin can lead to diarrhea or pseudomembranous colitis caused by Clostridium difficile.

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Can dicloxacillin interact with other medications?

When taking dicloxacillin it is necessary to take into account that, as we have already said, Dicloxacillin is a penicillin. It has been described that penicillins can reduce the excretion of methotrexate when consumed together. This reduction in the excretion of the drug may lead to an increase in its toxicity.

Further, penicillins can interact with oral contraceptives, decreasing its effectiveness and therefore increasing the risk of pregnancy.

Pregnancy, lactation and dicloxacillin

To date, clinical experience seems to indicate little risk during pregnancy, the fetus or the newborn. However, Ideally, assess the risk / benefit existing before the start of dicloxacillin treatment.

In the case of breastfeeding, it seems that penicillins are excreted in a very low proportion in breast milk, which is unlikely to show harmful effects. In the same way, the risk / benefit evaluation by the doctor is the most advisable.

However, dicloxacillin It is frequently used for the treatment of mastitis in nursing mothers and, occasionally, the baby's oral and intestinal microbiota could be affected, leading to episodes of diarrhea.

However, this effect seems to have not been adequately studied and Penicillin treatment during breastfeeding continues to be compatible.

The use of dicloxacillin in pregnancy is considered safe. To date there are no investigations that show that it causes relevant risks in the river or fetus.

Side effects of dicloxacillin

Antibiotics are primarily associated with adverse effects related to gastrointestinal disorders, such as:

  • Sickness
  • Vomiting
  • Diarrhea
  • Flatulence
  • Epigastric pain and even halitosis

Also, like other penicillins, may cause allergic symptoms such as hives, itching, rash cutaneous or anaphylactic reaction in case of severe allergy.

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It is important that you keep in mind that antibiotics are indicated in the treatment of bacterial infections and are not effective in cases of viral infections.

For the above, the use of antibiotics to treat a cold or flu is not going to be effective and, in addition, we run the risk of creating resistance. Always consult the doctor.