bromocriptine

Bromocriptine is a semi-synthetic compound derived from ergotamine. Ergotamine is a natural alkaloid produced by the ascomycete Claviceps purpurea . This fungus - also known as Ergot - is a grassy parasite and mainly affects rye. When the rye is infested with this fungus, it is called ergot .

Bromocriptine - Chemical Structure

Indications

For what it uses

Bromocriptine is indicated for the treatment of:

Prolactin-secreting pituitary adenomas (the hormone responsible for stimulating the mammary glands and lactation);
Hyperprolactinemia, ie the presence of elevated prolactin blood concentrations;
Galactorrhea, ie the abnormal secretion of milk in women who are not breastfeeding;
Prolige-dependent amenorrhea;
Menstrual dysfunctions;
Acromegaly, which can cause abnormal hair growth in women;
Male proleptic-dependent hypogonadism;
Malignant neuroleptic syndrome;
Parkinson's disease.

Furthermore, bromocriptine was approved in 2009 by the FDA (Food and Drug Administration) for the treatment of type 2 diabetes; however, the mechanism by which it is able to exert a glycemic control action is not entirely clear.

Warnings

Bromocriptine therapy should be performed under strict medical supervision.

Women taking the drug should undergo regular gynecological examinations.

Cases of gastrointestinal bleeding have been reported in some acromegalic subjects; therefore, patients on bromocriptine therapy - with a history of peptic ulcer disease or an ongoing peptic ulcer - should preferably receive another type of treatment.

Much attention must be paid to the administration of bromocriptine in parkinsonian patients who have a history of psychotic disorders, cardiovascular disorders, peptic ulcer and / or gastrointestinal bleeding.

When bromocriptine is administered to women for the treatment of diseases that are not related to hyperprolactinaemia, the least amount of drug should be used, in order to avoid lowering prolactin below the normal rate.

Bromocriptine can cause drowsiness and / or induce sudden sleep attacks, therefore, patients taking the drug should avoid driving vehicles or using machines.

Because of its pulmonary toxicity, caution should be exercised in the administration of bromocriptine in patients with pleuropulmonary disorders of an unknown nature.

Bromocriptine should not be used routinely to prevent or stop milk production, but should only be used in actual case of need and only after medical advice. Furthermore, the drug should not be used in affected women - or those who have been affected - by hypertensive diseases, heart conditions and / or severe psychiatric disorders.

Interactions

Bromocriptine is a drug with an agonist action against dopaminergic receptors (dopamine receptors). As a result, dopamin antagonist drugs and antipsychotic drugs could reduce the effect of bromocriptine.

Treatment with ergot alkaloids - or with other drugs acting on blood pressure - together with the administration of bromocriptine, could cause an enhancing effect. A lot of caution should therefore be used in the simultaneous use of these drugs.

The use of macrolides (drugs with antibiotic action) in combination with bromocriptine, can increase their plasma concentration producing potentially dangerous effects.

The response to bromocriptine therapy may be decreased if given concurrently with griseofulvin (an antifungal drug).

Tolerance to treatment with bromocriptine may be reduced by alcohol consumption.

Side effects

Bromocriptine - like any other drug - can induce various types of side effects. Each individual responds differently to therapy, so not all side effects must all occur with the same intensity in each patient.

The following are the main adverse effects that may occur following treatment with bromocriptine:

Psychiatric disorders

Bromocriptine therapy can cause psychomotor excitement, confusion and hallucinations .

Nervous system disorders

During the intake of bromocriptine it is very common the appearance of disorders such as headache, dizziness and dyskinesia, characterized by uncontrollable muscular movements, loss of coordination and / or balance.

Furthermore - as previously mentioned - bromocriptine can cause drowsiness, excessive daytime sleepiness and sudden sleep attacks in the absence of warning signs, making it very dangerous to drive vehicles and / or use machinery.

Cardiac disorders

Treatment with bromocriptine can cause serious heart disease, including cardiac valvulopathies (ie heart valve disorders), pericarditis (ie inflammation of the pericardium, the membrane that covers the heart) and pericardial effusions (accumulation of fluid in the pericardial space, i.e. space between the pericardium and the heart).

Vascular pathologies

Bromocriptine therapy may favor the onset of orthostatic hypotension, ie a sudden drop in blood pressure following the transition from a lying or sitting position to an upright position.

Bromocriptine can also induce hypertension accompanied by symptoms such as severe headache, ringing in the ears, blurred vision, anxiety, confusion, chest pain, shortness of breath, irregular heartbeat and seizure.

Gastrointestinal disorders

Treatment with bromocriptine can cause disorders such as stomach pain, loss of appetite, nausea, vomiting, diarrhea and constipation . Bloody stools may also appear. Furthermore, bromocriptine could cause gastrointestinal bleeding.

Raynaud's syndrome

Bromocriptine therapy may cause Raynaud's phenomenon. This phenomenon is characterized by an excessive spasm of peripheral blood vessels which causes a reduction in blood flow in the affected areas. The phenomenon occurs mostly in the fingers and toes, but can also involve other parts of the body. The skin of the affected areas usually takes on a yellow color that can become cyanotic and, finally - once the blood has been restored - it turns red.

Pleuropulmonary disorders

Bromocriptine can cause pleural effusions and pleuropulmonary fibrosis ; these side effects occurred mainly after long-term and high-dose treatments.

Bromocriptine can also trigger coughing with blood or vomiting.

Impulse control disorders

Bromocriptine therapy can cause serious impulse control disorders. These disorders include compulsive shopping or excessive shopping, pathological gambling, increased libido, hypersexuality, bulimia and the uncontrolled urge to eat.

Hypoglycemia

Bromocriptine may cause a decrease in blood glucose levels; this reduction could cause symptoms such as headaches, sweating, tremors, feelings of hunger, irritability and difficulty concentrating.

Other side effects

Other side effects that can occur after taking bromocriptine are:

Dry mouth;
Leg cramps;
Vision problems;
Nose constantly dripping or plugged nose;
Rhinitis;
Sinusitis;
Pain in the chest or during breathing;
Rapid breathing;
Shortness of breath;
Backache;
Localized swelling in ankles and feet;
Weakness;
Fatigue.

Overdose

Treatment of bromocriptine overdose is only symptomatic. Metoclopramide can be used to treat vomiting and hallucinations.

Action mechanism

Bromocriptine is a dopaminergic receptor agonist and - as such - is able to mimic the biological effects of dopamine. In particular, bromocriptine has a high affinity for type 2 dopaminergic receptors (D2 receptors) located on the luteotropic cells of the adenohypophysis, responsible for prolactin release. By inhibiting the release of prolactin upstream, bromocriptine is thus able to interrupt the performance of the biological functions connected to it.

However - although prolactin inhibition is the main function of bromocriptine - it is also able to interact with dopaminergic neurons present in the nigrostriatal area of the brain. In patients suffering from Parkinson's disease - in addition to a degeneration of these neurons - there is also a decipherment of the enzymes responsible for the synthesis of dopamine. This is why - for the treatment of this disease - drugs are used that can act directly on dopaminergic receptors, such as bromocriptine.

Mode of Use - Posology

Bromocriptine is available for oral administration as tablets with different dosages. The drug should always be taken at mealtimes.

The bromocriptine dosage must be established by the doctor based on the type of pathology to be treated.

In general, for disorders that involve dysfunctions of the menstrual cycle and galactorrhoea, the recommended dose is half a tablet - containing 2.5 mg of active ingredient - to be taken two or three times a day.

In the case of the treatment of Parkinson's disease, on the other hand, the usual dose of bromocriptine is increased to 30 mg a day when used as monotherapy and 5-15 mg a day if used in combination with other drugs.