Home Medicines Metoclopramide: effect, areas of application, side effects

Metoclopramide: effect, areas of application, side effects

by Josephine Andrews
Published: Last Updated on 268 views

The active ingredient metoclopramide is used to treat nausea and vomiting. Because it stimulates the gastrointestinal movement, it also speeds up digestion. Long-term and high-dose use can lead to so-called dyskinesia (certain forms of movement disorders). As a result, numerous high-dose metoclopramide drops lost their approval in 2014. Here you can read everything interesting about metoclopramide.

How metoclopramide works

The active ingredient metoclopramide (MCP) has a stimulating effect on gastric emptying and passage through the small intestine (prokinetic) and reduces nausea (antiemetic).

The human body sometimes protects itself from the absorption of toxic substances via the digestive tract by vomiting. As soon as certain substances enter the blood via the gastric or intestinal mucosa , they are transported via the bloodstream to the so-called extended spinal cord ( medulla oblongata ).

This is where the vomiting center is located. It has a special area: the so-called chemoreceptor trigger zone with numerous docking points (receptors) for a wide variety of messenger substances. Harmful substances can be registered here directly by the vomiting center (there is no blood-brain barrier in this area ). The body responds with nausea and vomiting to avoid further absorption of the harmful substance.

With the help of certain drugs, receptors in this chemoreceptor trigger zone can be inhibited and thus nausea and vomiting suppressed. These active substances include metoclopramide:

MCP inhibits the dopamine D2 receptors and, in higher doses, also certain serotonin receptors. Dopamine and serotonin are important neurotransmitters.

In addition, metoclopramide also causes a faster gastrointestinal passage, which is used, for example, in certain combination products against migraines . This ensures that the active ingredient that relieves pain gets more quickly from the stomach into the intestines , where it can be absorbed into the blood.

intake, degradation and excretion

After ingestion, MCP is quickly absorbed into the blood through the intestinal wall and reaches the highest blood levels after about an hour. The active ingredient is mostly broken down by the liver and excreted in the urine.

In this way, about 80 percent of the active ingredient is eliminated from the body. In the case of renal dysfunction, however, this process is slowed down.

When is metoclopramide used?

MCP is used for:

  • Prevention and treatment of nausea and vomiting
  • Therapy of disorders of the gastrointestinal movement (motility disorders)

The duration of treatment should be kept as short as possible. It must not exceed five days.

How metoclopramide is used

Preparations with metoclopramide are available in many dosage forms. On the one hand, there are preparations to be used orally (drops, tablets, capsules). Adults usually take ten milligrams three times a day before meals with a glass of water.

On the other hand, the active ingredient can also be administered in the form of syringes (injections) and suppositories. This is particularly advantageous in the case of severe vomiting – oral preparations would then not remain in the body long enough to allow the active substance to be absorbed into the blood.

What are the side effects of metoclopramide?

During therapy with metoclopramide (MCP), more than ten percent of all those treated experience drowsiness and tiredness .

In addition, side effects such as diarrhea , weakness, depression, low blood pressure and – especially in children – extrapyramidal movement disorders (dyskinesia) appear in one in ten to one hundred people treated . These are movement disorders, especially in the facial area, which in rare cases occur with a delay and can be irreversible.

Occasionally, a drop in blood pressure or an excess of prolactin in the blood (hyperprolactinaemia) can be observed as a result of MCP intake.

What should be considered when taking metoclopramide?

Contraindications

Metoclopramide must not be used in:

  • gastrointestinal bleeding
  • Pheochromocytoma (rare tumor of the adrenal medulla)
  • known extrapyramidal movement disorders
  • Parkinson’s disease
  • Methaemoglobinemia (increased amount of methemoglobin in the blood = derivative of hemoglobin , which, unlike the latter, cannot bind oxygen)

interactions

Metoclopramide must not be used with drugs used to treat dopamine-deficiency diseases (such as Parkinson’s disease) that are thought to cause higher levels of dopamine in the brain . MCP would namely weaken their effect.

Drugs with a central depressant effect, such as strong painkillers, antiallergic agents, sedatives and sleeping pills, and alcohol, can increase the depressant effect of metoclopramide.

Concomitant use with antipsychotics (drugs prescribed for psychosis , delusions and schizophrenia , for example) can increase the risk of dyskinesia.

If MCP is combined with other active ingredients that lead to increased serotonin levels in the brain, life-threateningly high serotonin levels and the so-called serotonin syndrome (acute life-threatening condition with tachycardia , fever , nausea, vomiting, etc.) can occur. This applies, for example, to antidepressants (esp. SSRI), some painkillers, migraine remedies and tryptophan (a light sleep-inducing agent).

Metoclopramide increases the availability of ciclosporin (immunosuppressant) and decreases the availability of digoxin (medicine for heart failure) and oral contraceptives (” the pill “).

MCP is broken down in the liver with the participation of the enzyme CYP2D6. CYP2D6 inhibitors (e.g. fluoxetine , paroxetine) can therefore increase the effects and side effects of metoclopramide. Conversely, CYP2D6 inducers (including dexamethasone , rifampicin ) can weaken the effect of MCP.

age restriction

Metoclopramide tablets are approved from the age of nine. Drops and suppositories are available for children over one year old.

pregnancy and breast feeding period

Several tens of thousands of evaluated pregnancies under metoclopramide therapy show neither an increased risk of spontaneous abortion nor an increased overall malformation rate. The active ingredient can therefore be taken during pregnancy. To be on the safe side, the duration of the treatment should be kept as short as possible.

MCP may be used for short periods while breastfeeding. With prolonged therapy, there is a possibility that the active substance will pass into breast milk and lead to side effects in the infant (e.g. flatulence , slightly increased prolactin levels).

How to get medication with metoclopramide

All preparations with the active ingredient metoclopramide require a prescription in Germany, Austria and Switzerland. High-dose MCP drops (4mg/ml) have not been approved since 2014. Lower dose drops (1mg/ml) are still available.

The suppositories and retard capsules (capsules with delayed release of active ingredients) available in Germany are not on the market in Switzerland and Austria.

Since when is metoclopramide known?

Metoclopramide was first manufactured in 1964. The preparations that have been on the German pharmaceutical market for the longest time received their first approval in 1979. There are now numerous generics with the active ingredient.

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