Ropinirole

Ropinirole

Systematic (IUPAC) name
4-[2-(dipropylamino)ethyl]-1,3-dihydro-2H-indol-2-one
Clinical data
Trade names	Requip
AHFS/Drugs.com	monograph
MedlinePlus	a698013
Pregnancy cat.	C
Legal status	℞ Prescription only
Routes	Oral
Pharmacokinetic data
Bioavailability	50%[1]
Metabolism	Hepatic (CYP1A2)[1]
Half-life	5-6 hours[1]
Identifiers
CAS number	91374-21-9 Y
ATC code	N04BC04
PubChem	CID 5095
DrugBank	DB00268
ChemSpider	4916 Y
UNII	030PYR8953 Y
KEGG	D08489 Y
ChEBI	CHEBI:8888 Y
ChEMBL	CHEMBL589 Y
Chemical data
Formula	C16H24N2O
Mol. mass	260.375 g/mol
SMILES	eMolecules & PubChem
InChI InChI=1S/C16H24N2O/c1-3-9-18(10-4-2)11-8-13-6-5-7-15-14(13)12-16(19)17-15/h5-7H,3-4,8-12H2,1-2H3,(H,17,19) Y Key:UHSKFQJFRQCDBE-UHFFFAOYSA-N Y
Y (what is this?)  (verify)

Ropinirole (INN; trade names Requip, Ropark, Adartrel) is a non-ergoline dopamine agonist. It is manufactured by GlaxoSmithKline (GSK), Cipla and Sun Pharmaceutical. It is used in the treatment of Parkinson's disease. Ropinirole is one of three medications approved by the FDA to treat Restless Leg Syndrome, the other two being pramipexole (Mirapex) and gabapentin enacarbil (Horizant). The discovery of the drug's utility in RLS has been used as a successful example of drug repurposing.^[2]

Ropinirole's patent expired in May 2008, and the drug is now available in generic form.^[3]

Medical uses

Ropinirole is prescribed for mainly Parkinson's disease, restless leg syndrome, and extrapyramidal symptoms. It can also reduce the side effects caused by selective serotonin reuptake inhibitors, including Parkinsonism syndrome as well as sexual dysfunction and erectile dysfunction caused by either SSRIs or antipsychotics.

Dosage

Ropinirole in the Requip form is available in various preparations, ranging from a 0.25 mg tablet to a 5 mg tablet. The primary reason is dose titration. This implies that the person taking Requip has to closely interact and communicate with the primary care physician with regard to how much should actually be taken by the patient.

For restless leg syndrome (RLS), the maximum recommended dose is 4 mg per day, taken 1 to 3 hours before bedtime. A 52-week open label study had a mean dosage of 1.90 mg, once daily 1 to 3 hours before bedtime.^[4]

For Parkinson's disease (PD), the maximum recommended dose is 24 mg per day, taken in three separate doses spread throughout the day. The maximum dose recommendations of ropinirole for subjects with ESRD should be reduced by 25% compared with those recommended for subjects with normal renal function. A 25% dose reduction represents a more straightforward dosage regimen in terms of available tablet strength, compared with a 30% dose reduction.^[5]

Pharmacology

Ropinirole acts as a D₂, D₃, and D₄ dopamine receptor agonist with highest affinity for D₂. It is weakly active at the 5-HT₂, and α₂ receptors and is said to have virtually no affinity for the 5-HT₁, benzodiazepine, GABA, muscarinic, α₁, and β-adrenoreceptors.^[6]

Ropinirole is metabolized primarily by cytochrome P450 CYP1A2 to form two metabolites; SK&F-104557 and SK&F-89124, both of which are renally excreted^[5], and at doses higher than clinical, is also metabolized by CYP3A4. At doses greater than 24 mg, CYP2D6 may be inhibited, although this has only been tested in vitro.^[1]

Side effects

Ropinirole can cause nausea, dizziness, hallucinations, orthostatic hypotension, and sudden sleep attacks during the daytime. Common and more unusual side effects specific to D₃-preferring agonists such as ropinirole and pramipexole can include hypersexuality and compulsive gambling, even in patients without a prior history of these behaviours.^[7]

See also

• Piribedil
• Pramipexole
• Rotigotine

References

External links

• Requip for RLS
• Requip for PD
• Requip - Clinical Pharmacology