chemistry

Laropiprant

Laropiprant is a chemistry topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Laropiprant rather than just read about it. In short: Laropiprant (INN) was a drug used in combination with nicotinic acid to reduce blood cholesterol (LDL and VLDL) that is no longer sold, due to increases in side-effects with no cardiovascular benefit. Laropiprant itself has no cholesterol lowering effect, but it reduces facial flushes induced by nicotinic acid.

Key takeaways

Laropiprant belongs to chemistry; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Laropiprant to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Laropiprant from memory before moving on to harder problems.

Reference excerpt

Laropiprant (INN) was a drug used in combination with nicotinic acid to reduce blood cholesterol (LDL and VLDL) that is no longer sold, due to increases in side-effects with no cardiovascular benefit. Laropiprant itself has no cholesterol lowering effect, but it reduces facial flushes induced by nicotinic acid. Merck & Co. planned to market this combination under the trade names Cordaptive in the US and Tredaptive in Europe. Both brands contained 1000 mg of nicotinic acid (niacin) and 20 mg of laropiprant in each tablet.

Mechanism of action Nicotinic acid in cholesterol lowering doses (500–2000 mg per day) causes facial flushes by stimulating biosynthesis of prostaglandin D2 (PGD2), especially in the skin. PGD2 dilates the blood vessels via activation of the prostaglandin D2 receptor subtype DP1, increasing blood flow and thus leading to flushes. Laropiprant acts as a selective DP1 receptor antagonist to inhibit the vasodilation of prostaglandin D2-induced activation of DP1. Taking 325 mg of aspirin 20–30 minutes prior to taking nicotinic acid has also been proven to prevent flushing in 90% of patients, presumably by suppressing prostaglandin synthesis, but this medication also increases the risk of gastrointestinal bleeding, though the increased risk is less than 1 percent.

History In the mid-2000s, in a trial with 1613 patients, 10.2% patients stopped taking the medication in the combination drug group versus 22.2% under nicotinic acid monotherapy. On April 28, 2008, the U.S. Food and Drug Administration (FDA) issued a "not approved" letter for Cordaptive. Tredaptive was approved by the European Medicines Agency (EMA) on July 3, 2008. On January 11, 2013, Merck & Co Inc. announced they were withdrawing the drug worldwide as a result of European regulators recommendations. The Heart Protection Study 2-Treatment of HDL to Reduce the Incidence of Vascular Events (HPS2-THRIVE) involved more than 25,000 adults. The treatment group received 2 g of extended-release nicotinic acid and 40 mg of laropiprant daily. Study results, reported in July 2014, showed that the combination of nicotinic acid and laropiprant did not have any beneficial effects when compared with a placebo treatment and had an increase in adverse effects.

References

Illustrations

Worked examples

Example 1 — a first encounter with Laropiprant

Start with the simplest possible case. Write down what Laropiprant claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In chemistry, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Laropiprant before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Laropiprant ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Laropiprant

In research: Laropiprant appears in chemistry research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Laropiprant in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Laropiprant is common in secondary-school and first-year university syllabi. It links to neighbouring topics 4-Chlorophenyl compounds, Acetic acids, Combination lipid-lowering drugs, so understanding it makes those chapters shorter.
In everyday life: Look for Laropiprant outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Laropiprant in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Laropiprant means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Laropiprant out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Laropiprant in simple terms?

Why does Laropiprant matter?

Because it connects several chemistry ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Laropiprant?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Laropiprant.