What Is Pizotifen?
Pizotifen is a medication that belongs to the class of drugs known as tricyclic antidepressants. However, it is more commonly used for its antiserotonergic and antihistaminic properties rather than its antidepressant effects. It is primarily prescribed for the prevention of migraines and other vascular headaches.
Pizotifen is well absorbed from the gastrointestinal tract, with peak plasma concentrations occurring about 5 hours after a single oral dose. Over 90% is bound to plasma proteins. Pizotifen undergoes extensive metabolism. Over half of a dose is excreted in the urine, chiefly as metabolites; a significant proportion is excreted in the feces. The primary metabolite of pizotifen (N-glucuronide conjugate) has a long elimination half-life of about 23 hours.
Distribution into milk has been found in animal studies.
Key points about Pizotifen include:
- Migraine Prevention: Pizotifen is often used to reduce the frequency and severity of migraines. It is thought to work by affecting the levels of certain neurotransmitters, including serotonin and histamine.
- Antiserotonergic and Antihistaminic Effects: Pizotifen blocks serotonin and histamine receptors (5-HT receptors). This dual action contributes to its effectiveness in preventing migraines.
- Other Uses: Besides migraine prevention, Pizotifen has been explored for its potential in managing other conditions, including tension-type headaches and certain behavioral disorders.
- Not for Acute Treatment: Pizotifen is not typically used for the acute treatment of migraines or headaches. It is more of a preventive measure and needs to be taken regularly to be effective.
If you have concerns about its use or potential side effects, discussing them with your doctor is best. They can provide guidance based on your individual health needs and conditions.
Adverse Effects and Precautions
Common side effects of Pizotifen may include:
- Drowsiness: Pizotifen can cause drowsiness or sedation, so taking it at bedtime is often recommended to minimize this effect.
- Weight Gain: Some individuals may experience weight gain or increased appetite while taking Pizotifen.
- Dry Mouth: Dry mouth is a common side effect of many medications, including Pizotifen.
- Increased Appetite: An increase in appetite, which can contribute to weight gain, is a reported side effect.
- Dizziness: Pizotifen may cause dizziness, especially when standing up quickly. It’s essential to stand up slowly from a sitting or lying position.
- Blurred Vision: Some people may experience blurred vision as a side effect.
- Constipation: Pizotifen can cause constipation in some individuals.
- Nausea: Nausea is another potential side effect.
Not everyone will experience these side effects, and some individuals may experience side effects not listed here. Additionally, serious side effects can occur, although they are less common. If you experience severe side effects or have concerns about the medication, you must contact your healthcare provider promptly.
Incidence of Adverse Effects
Adverse effects were noted in 22 of 47 patients with severe migraines given pizotifen 1 to 2 mg daily. These reactions included weight increase (15), muscle pain or cramps (3), heavy or restless legs (3), fluid retention (3), drowsiness (2), more frequent milder headaches (2), facial flushing (1), reduced libido (1), exacerbation of epilepsy (1), and dreaming (2). Adverse effects necessitating withdrawal occurred in 11 patients.
Pizotifen can interact with other medications and substances, potentially affecting its effectiveness or increasing the risk of side effects. It’s crucial to inform your healthcare provider about all the medications, supplements, and herbal products you are taking. Some potential interactions with Pizotifen include:
- Sedatives and Alcohol: Pizotifen can enhance the sedative effects of other medications and alcohol. Combining it with sedatives or alcohol may increase drowsiness and impair coordination.
- Antihistamines: Pizotifen has antihistaminic properties, so combining it with other medications that have similar effects may lead to increased sedation and drowsiness.
- Monoamine Oxidase Inhibitors (MAOIs): Concomitant use of Pizotifen with MAOIs can increase the risk of serotonin syndrome, a potentially life-threatening condition characterized by symptoms like confusion, hallucinations, seizure, extreme changes in blood pressure, increased heart rate, fever, excessive sweating, shivering, blurred vision, muscle spasm or stiffness, tremor, incoordination, stomach cramp, nausea, vomiting, and diarrhea.
- Selective Serotonin Reuptake Inhibitors (SSRIs): Combining Pizotifen with SSRIs or other medications that affect serotonin levels may increase the risk of serotonin syndrome.
- Tricyclic Antidepressants: Concurrent use of Pizotifen with tricyclic antidepressants may enhance sedation and anticholinergic effects.
- Anticholinergic Medications: Pizotifen has anticholinergic effects, and combining it with other medications with anticholinergic properties may lead to an additive effect, causing symptoms such as dry mouth, blurred vision, constipation, and urinary retention.
Always consult your healthcare provider before starting or stopping any medication. Tell them your complete medical history and all the substances you are taking to ensure a safe and effective treatment plan.
Dosage and Administration
Pizotifen is a sedating antihistamine with a potent serotonin antagonist and weak antimuscarinic properties. It also antagonizes the action of tryptamine. Pizotifen is used, usually as the malate, for migraine prevention and preventing headache attacks during cluster periods. It is not effective in treating an acute attack. Doses of pizotifen malate are expressed in terms of the base; pizotifen malate 1.45 mg is equivalent to about 1 mg of pizotifen. The usual adult oral dose is 1.5 mg daily, either in three divided doses or as a single dose at night; children over two years may also be given up to 1.5 mg daily, although the maximum single dose (at night) should not exceed 1 mg.
The gradual increase from an initial dose of 500 micrograms may help to avoid undue drowsiness. Doses in adults may vary from 500 micrograms up to a maximum of 4.5 mg daily; not more than 3 mg should be given as a single dose. Pizotifen hydrochloride has also been used in the management of migraine.
Abdominal migraine is a recurrent disorder seen mainly in children and characterized by episodic mid-line abdominal pain lasting up to 72 hours. The pain is severe enough to disrupt normal activities and may be associated with pallor, anorexia, nausea, and vomiting. Sleep and sometimes vomiting terminate the attack.
Pizotifen was effective in preventing abdominal pain in children with abdominal migraine. Prophylactic treatment with propranolol or cyproheptadine may also be of benefit.
Migraine and Cluster Headache
Pizotifen has been widely used to prevent migraine, but evidence for its efficacy is limited. It has also been tried to manage cluster headaches to prevent headache attacks during a cluster period.
(British Approved Name, rINN)
Synonyms: BC-105; Pitsotifeeni; Pizotifen; Pizotifeno; Pizotifenum
INN: Pizotifen [rINN (en)]
INN: Pizotifeno [rINN (es)]
INN: Pizotifène [rINN (fr)]
INN: Pizotifenum [rINN (la)]
INN: Пизотифен [rINN (ru)]
Chemical name: 9,10-Dihydro-4-(1-methylpiperidin-4-ylidene)-4H-benzo[4,5]cyclohepta[1,2-b]thiophene
Molecular formula: C19H21NS =295.4
ATC code: N02CX01
Read code: y041E
Pharmacopoeias. In China.
(British Approved Name Modified, rINNM)
Synonyms: Pizotifen Hydrogen Malate; Pizotifeno, malato de; Pizotyline Malate
BAN: Pizotifen Malate [BANM]
INN: Pizotifen Malate [rINNM (en)]
INN: Malato de pizotifeno [rINNM (es)]
INN: Pizotifène, Malate de [rINNM (fr)]
INN: Pizotifeni Malas [rINNM (la)]
INN: Пизотифена Малат [rINNM (ru)]
Molecular formula: C19H21NS,C4H6O5 =429.5
ATC code: N02CX01
Pharmacopoeias. In British.
British Pharmacopoeia 2008 (Pizotifen Malate). A white or slightly yellowish-white, odorless or almost odorless, crystalline powder. Very slightly soluble in water, slightly soluble in alcohol and chloroform, sparingly soluble in methyl alcohol. Protect from light.
British Pharmacopoeia 2008: Pizotifen Tablets.
The symbol ¤ denotes a preparation, which is discontinued or no longer actively marketed.
Belgium: Mosegor¤; Sandomigran;
Czech Republic: Sandomigran;
Germany: Mosegor; Sandomigran¤;
Hong Kong: Sandomigran;
New Zealand: Sandomigran;
South Africa: Sandomigran;
Spain: Mosegor; Sandomigran;
Switzerland: Mosegor; Sandomigran¤;
Thailand: Anorsia; Mosegor; Moselar; Pizomed; Zofen;
United Kingdom: Sanomigran;