Allopurinol: Side Effects And Indications
Allopurinol is a drug prescribed to treat gout and high uric acid levels in the body. It is given in cases where gout is due to the side effects of other drugs, such as those for cancer or kidney stones.
Its action is expressed in the ability to reduce the synthesis of uric acid, responsible for the clinical symptoms of gout. Allopurinol belongs to the family of drugs known as xanthine oxidase inhibitors, an enzyme required for uric acid synthesis. We will look at this process in more detail in the next few lines.
However, it is important to emphasize that allopurinol does not cure gout attacks, but is taken as a prevention method in case the patient undergoes treatment with other drugs such as those mentioned.
What is gout?
Gout has been a known disease for centuries. It tends to manifest itself as an acute joint-type inflammation, usually located on the big toe. In other words, gout causes asymptomatic inflammation in a joint, which swells and causes pain for a short period of time.
Inflammation is caused by the presence of monosodium urate crystals, a substance formed by an excess of uric acid in the blood. High levels of this acid are generally linked to bad lifestyle habits, such as an unbalanced diet (excessive amounts) and alcohol intake. Once these levels have normalized, the crystals tend to dissolve naturally.
People with high uric acid levels are diagnosed with hyperuricaemia. However, although this condition is common (7% of men suffer from it), only a small number of people develop the characteristic crystals of gout.
When the gout attack ends, the monosodium urate crystals remain in the joint. Following this, even if treatment has been performed, another gout attack can occur at any time.
Adverse reactions of allopurinol
Adverse reactions are more frequent in patients with renal or hepatic insufficiency. The reason is that allopurinol is metabolized in the liver and excreted via the kidney. Due to these changes, the concentrations of the drug in the body can increase or decrease.
When it increases, so do its effects. In this way, it is easier for the patient to suffer from adverse reactions. Let’s take a look at the most common side effects of this medicine.
Skin reactions
They are the most common and can occur at any time during treatment with allopurinol. Among them we remember:
- Itch.
- Desquamation.
- Purpuric lesions.
- Exfoliation.
- Skin rash.
If one or more symptoms occur, treatment with this medicine should be stopped. Once healed, treatment can be resumed by gradually increasing the dose. However, if a skin rash occurs, the treatment will have to be stopped permanently.
Generalized hypersensitivity reactions to allopurinol
Although infrequent, hypersensitivity reactions can occur. In these cases the patient may accuse:
- Temperature.
- Stevens-Johnson or Lyell syndrome.
- Lymphadenopathy.
- Vasculitis: It can manifest itself in a number of ways including hepatitis, nephritis and epilepsy.
If such reactions occur, allopurinol treatment should be discontinued immediately and forever. In these cases, corticosteroids are usually given to cancel the symptoms of generalized hypersensitivity.
Allopurinol and gastrointestinal disorders
Regarding the alterations of the digestive system, the most common reactions are nausea and vomiting. To prevent them, it is recommended not to take allopurinol after meals.
Granulomatous hepatitis
This adverse reaction has been described on very rare occasions and without evidence of generalized hypersensitivity. Once treatment is stopped, the effect tends to subside.
Conclusion
Allopurinol is an effective drug in the prevention of gout attacks caused by the administration of other drugs. It is a prescription medicine, so self-medication should be avoided. Misuse of this drug can lead to the development of serious health problems.
If you have any doubts, information or if you have developed an adverse reaction, ask your doctor or pharmacist for advice.