Merlin

Merlin Uses, Dosage, Side Effects, Food Interaction and all others data.

Merlin is the difluorinated derivative of cinnarizine. It is a seletive calcium channel antagonist and has H1-receptor blocking action. By reducing excessive transmembrane influx of calcium Merlin prevents cellular calcium overlod. It does not interfere with normal cellular calcium homeostasis. Merlin also has some antihistaminic and sedative properties.

Merlin is a selective calcium entry blocker with calmodulin binding properties and histamine H1 blocking activity.

Trade Name Merlin
Generic Flunarizine
Flunarizine Other Names Flunarizina, Flunarizine, Flunarizinum
Type Tablet
Formula C26H26F2N2
Weight Average: 404.4948
Monoisotopic: 404.206405252
Protein binding

99% bound to plasma proteins

Groups Approved
Therapeutic Class Miscellaneous prophylactic migraine preparations
Manufacturer
Available Country India
Last Updated: September 19, 2023 at 7:00 am
Merlin
Merlin

Uses

Merlin is used for

  • Prophylaxis of classic (with aura) or common (without aura) migraine
  • Symptomatic treatment of vestibular vertigo (due to a diagnosed functional disorder of the vestibular system).
  • Peripheral Vascular Disease (PVD)
  • Motion sickness
  • Refractory epilepsy resistant to conventional antiepileptic therapy.

Merlin is also used to associated treatment for these conditions: Severe Migraine

How Merlin works

Merlin inhibits the influx of extracellular calcium through myocardial and vascular membrane pores by physically plugging the channel. The decrease in intracellular calcium inhibits the contractile processes of smooth muscle cells, causing dilation of the coronary and systemic arteries, increased oxygen delivery to the myocardial tissue, decreased total peripheral resistance, decreased systemic blood pressure, and decreased afterload.

Dosage

Merlin dosage

Migraine Prophylaxis:

  • Starting Dose: 10 mg at night in patients less than 65 years of age and 5 mg daily in patients older than 65 years. If, during this treatment depressive, extrapyramidal or other unacceptable symptoms occur, administration should be discontinued. If, after 2 months of this initial treatment, no significant improvement is observed, the patient should be considered a non-responder and administration should be discontinued.
  • Maintenance Treatment: If a patient is responding satisfactorily and if a maintenance treatment is needed, the dose should be decreased to 5 days treatment at the same daily dose with two successive medicine free days every week. Even if the prophylactic maintenance treatment is successful and well tolerated, it should be interrupted after 6 months and it should be re-initiated only if the patient relapses.

Peripheral Vascular disease: 10 mg twice daily, up to 30 mg per day if required.

Vertigo & motion sickness: 10-20 mg daily for adults and 5 mg daily for children (> 40 kg).

Epileptic seizure: 15-20 mg daily in adults and 5 to 10 mg daily for children as an add-on therapy

Side Effects

Merlin is well tolerated and seldom causes serious side effects. The main adverse effects experienced by the patients are as follows:

Central nervous system: Depression, drowsiness, sedation, and anxiety.

Gastrointestinal: Heart burn, nausea, emesis, dry mouth, gastralgia.

Miscellaneous: Weight gain, and/or increased appetite, asthenia, muscle aches, skin rash, and galactorrhea in female patients on oral contraceptives.

Toxicity

-Merlin should be used with care in patients with depression or those being prescribed other agents, such as phenothiazines, concurrently, which may cause extrapyramidal side-effects. -Acute overdosage has been reported and the observed symptoms were sedation, agitation and tachycardia. -Treatment of acute overdosage consists of charcoal administration, induction of emesis or gastric lavage, and supportive measures. No specific antidote is known.

Precaution

Since sedation or drowsiness occur in some patients during treatment with flunarizine hydrochloride, patients should be cautioned against activities which require alertness or rapid, precise responses (e.g. operating machinery or a motor vehicle) until the response to the drug has been determined.

Interaction

Galactorrhoea has been reported in few women on oral contraceptives within the first two months of Merlin treatment. Hepatic enzyme inducers such as Carbamazepine and Phenytoin may interact with flunarizine by increasing its metabolism. So an increase in dosage of flunarizine may be required.

Food Interaction

  • Avoid alcohol.
  • Take with or without food. The absorption is unaffected by food.

Elimination Route

85% following oral administration.

Half Life

18 days

Pregnancy & Breastfeeding use

Safety in pregnancy and lactation has not been established.

Contraindication

Hypersensitivity to Merlin. Merlin is contra-indicated in patients with a history of depressive illness, or with pre-existing symptoms of Parkinson's disease or other extrapyramidal disorders.

Storage Condition

Store at a cool & dry place, protected from light and moisture. Keep out of reach of the children.

Innovators Monograph

You find simplified version here Merlin

FAQ

What is Merlin used for?

Merlin is a selective calcium entry blocker with calmodulin binding properties and histamine H1 blocking activity. It is effective in the prophylaxis of migraine, occlusive peripheral vascular disease, vertigo of central and peripheral origin, and as an adjuvant in the therapy of epilepsy.


How safe is Merlin?

Merlin may be safe, effective, and well-tolerated as a prophylactic treatment for episodic migraine, according to a systematic review and pooled meta-analysis published in Pain.

How does Merlin work?

Merlin is a selective calcium entry blocker with calmodulin binding properties and histamine H1 blocking activity. Merlin inhibits the influx of extracellular calcium through myocardial and vascular membrane pores by physically plugging the channel.

What are the common side effects of Merlin?

The common side effects of Merlin are tiredness, drowsiness, weight gain and low mood. Possible weight gain is caused by an increase in appetite and can be avoided by your child following his or her usual diet without any increase in portion size.

Is Merlin safe during pregnancy?

Merlin probably is compatible with pregnancy.

Is Merlin safe during breastfeeding?

No information is available on the use of Merlin during breastfeeding.

Can I drink alcohol with Merlin?

Alcohol may increase the risk of tiredness and drowsiness with Merlin. If you do feel tired or drowsy whilst taking Merlin, you should avoid alcoholic drinks.

Can I drive after taking Merlin?

Merlin may cause drowsiness. If affected, do not drive or take part in any activity in which you need to be alert or need to see clearly.

When should be taken of Merlin?

Merlin should be taken at night-time starting with a low dose. This may then be increased as recommended by the doctor. You should encourage your child to continue with the medicine as it may not take full effect for about eight to 12 weeks.

How often can I take Merlin?

The recommended adult dose of Merlin is 10 mg daily taken in the evening with or without food. Those who have side effects may find 5 mg daily in the evening to be effective.

How long does Merlin take to work?

It may take 6 to 8 weeks of continued treatment before the maximum effect of this Merlin is noted.

How long does Merlin take to work?

Merlin has a long elimination half-life of about 19 days.

How long does Merlin last?

Merlin will usually be used for at least six months but you will be advised further about this by your doctor.

Who should not take Merlin?

Merlin should not be taken by people with depression or by people with Parkinson's disease or movement disorders.

Can Merlin increase blood pressure?

Merlin  is reported to produce only slight decreases of systemic arterial blood pressure.

Does Merlin cause depression?

In contrast, Merlin, a calcium-channel antagonist used for acute and prophylactic treatment of migraine headaches, has been associated with depression.

Can I just stop taking Merlin?

It is not advisable to stop using this product suddenly, particularly if you have been on it for several weeks. If you are considering stopping the medication, talk to your doctor or pharmacist first. It must be used regularly and continuously to maintain its beneficial effects.

What happen If I missed dose of Merlin?

If you miss a dose, take it as soon as remembered; do not take it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not double-up the dose to catch up.

What happens if I overdose?

Symptoms of overdose may include confusion, unusual drowsiness, and rapid pulse. 

Can Merlin affects my heart ?

Merlin caused an increase in heart rate following the administration of the higher doses.

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http://classyfire.wishartlab.com/tax_nodes/C0001031
http://classyfire.wishartlab.com/tax_nodes/C0002239
http://classyfire.wishartlab.com/tax_nodes/C0004139
http://classyfire.wishartlab.com/tax_nodes/C0004557
http://classyfire.wishartlab.com/tax_nodes/C0001517
http://classyfire.wishartlab.com/tax_nodes/C0004150
http://www.hmdb.ca/metabolites/HMDB0015589
http://www.genome.jp/dbget-bin/www_bget?drug:D01303
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=941361
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=46507129
https://www.chemspider.com/Chemical-Structure.819216.html
http://www.bindingdb.org/bind/chemsearch/marvin/MolStructure.jsp?monomerid=50017702
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=4459
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=135652
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL30008
https://zinc.docking.org/substances/ZINC000019360739
http://bidd.nus.edu.sg/group/cjttd/ZFTTDDRUG.asp?ID=DAP000142
http://www.pharmgkb.org/drug/PA164776636
https://www.drugs.com/international/flunarizine.html
https://en.wikipedia.org/wiki/Flunarizine
*** Taking medicines without doctor's advice can cause long-term problems.
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