ACTION AND MECHANISM

Xanthine base. Central nervous system stimulant. Its mechanism of action involves its ability to inhibit the phosphodiesterase enzyme, resulting in an increase in cAMP; at low doses, another mechanism predominates: it antagonizes adenosine receptors. It produces cardiac stimulation (positive inotropic effect) and a reduction in peripheral arteriolar resistance, which compensates for its effects on blood pressure. In the brain, it produces vasoconstriction, which has led to its suggestion for use as an antimigraine agent. It stimulates skeletal muscle and the respiratory center, and increases gastric acid secretion and diuresis.

SPECIAL WARNINGS

- Abrupt discontinuation of regular administration of doses above 600 mg/day may cause headache, anxiety, and muscle spasm.

SENIORS

The safety and efficacy of this medication in the elderly have not been fully established. However, although no specific serious problems are anticipated in this age group, these patients may be more sensitive to CNS side effects. Use with caution.

COMPOSITION

Per capsule: Caffeine, 300 mg.

PATIENT ADVICE

- Do not take the last dose within 6 hours of bedtime to avoid possible insomnia. - Swallow the capsules whole, without chewing or crushing them. - Do not take more than 3 capsules per day. - If symptoms worsen or persist after 7 days, your clinical situation will be evaluated.

CONTRAINDICATIONS

- Caffeine allergy or [XANTHINE ALLERGY].- Serious cardiovascular disorders ([CARDIAC ARRHYTHMIA], [HEART FAILURE], [CORONARY INSUFFICIENCY]): due to the risk of tachycardia and extrasystoles.- [EPILEPSY]: increases the risk of seizures.- [INSOMNIA]: due to its stimulating activity on the central nervous system.- [PEPTIC ULCER]: due to its increasing effect on gastric acid secretion.

PREGNANCY

FDA Pregnancy Category C. Animal studies using doses equivalent to 12-14 cups of coffee per day throughout pregnancy or very large single doses have shown teratogenic effects; lower doses have been associated with skeletal developmental delays. Caffeine crosses the placenta, reaching fetal serum and tissue concentrations similar to maternal levels. The safety of caffeine use during pregnancy has not been established. Excessive caffeine consumption has been weakly associated with an increased incidence of fetal loss, low birth weight, and premature birth, although a clear causal relationship has not been established. However, moderate use does not appear to be associated with these effects or with congenital malformations. Pregnant women are advised to limit or avoid foods, beverages, and medications containing caffeine.

PHARMACOKINETICS

* Oral route: - Absorption: Rapidly absorbed (Tmax = 50-75 min). - Distribution: Rapidly distributed throughout the body. Plasma protein binding: 15-30%. - Metabolism: Almost entirely hepatic via oxidation, demethylation, and acetylation. - Elimination: Excreted in the urine, <1% unchanged. The elimination half-life (t1/2) is 3-6 h (adults), 80-100 h (newborns), 4-5 h (hepatic impairment); it decreases in smokers and athletes, and is not altered in the elderly or during pregnancy.

INDICATIONS

- [ASTHENIA]. Symptomatic and occasional relief of transient states of asthenia.

INTERACTIONS

- Oral contraceptives (estrogens): Studies have shown decreased caffeine clearance, with possible potentiation of its effects and/or toxicity, due to inhibition of its hepatic metabolism. - Cimetidine: Studies have shown decreased caffeine clearance, with possible potentiation of its effects and/or toxicity, due to inhibition of its hepatic metabolism. - Clozapine: Some studies have shown inhibition of the antipsychotic effect of clozapine, due to antagonism of its actions at dopamine receptors. - Disulfiram: Some studies have shown decreased caffeine clearance, with possible potentiation of its effects and/or toxicity, due to possible inhibition of its hepatic metabolism. - Methoxsalen: Some studies have shown decreased caffeine clearance, with possible potentiation of its effects and/or toxicity, due to inhibition of its hepatic metabolism. - Mexiletine: studies have shown a decrease in caffeine clearance, with possible potentiation of its action and/or toxicity. - Quinolones (pipemidic acid, ciprofloxacin, enoxacin): studies have shown an increase in plasma caffeine levels, with possible potentiation of its action and/or toxicity, due to inhibition of its hepatic metabolism.

LACTATION

Caffeine is excreted in breast milk in small amounts (milk/plasma ratio of 0.5) and can accumulate in the infant. When a breastfeeding mother consumes 6-8 cups of caffeinated beverages, the infant may show symptoms of caffeine stimulation (hyperactivity and wakefulness). It is recommended that breastfeeding mothers limit their intake of caffeinated beverages to 1-2 cups/day or less and avoid taking caffeine capsules or tablets. Combinations of analgesics with caffeine, at recommended doses, produce negligible concentrations in the infant.

CHILDREN

The safety and efficacy of this medication in children under 12 years of age have not been established. Central nervous system (CNS) adverse effects are generally more severe in children than in adults. Use is not recommended in children under 12 years of age.

GUIDELINES FOR PROPER ADMINISTRATION

* Oral route: Take the capsules whole, making sure to administer the last dose 6 hours before going to bed, to avoid possible insomnia.

POSOLOGY

* Asthenia: - Adults and children over 12 years of age, oral: 300 mg in one or more doses. Maximum dose: 900 mg/24 h. If symptoms worsen or persist for more than 7 days, the clinical situation should be evaluated. - Children under 12 years of age: should not be used.

PRECAUTIONS

- [DIABETES]: May cause an increase in plasma glucose levels. - [HIGH BLOOD PRESSURE]: Blood pressure should be monitored due to the possibility of an increase. - [HEPATIC INSUFFICIENCY]: Since it is mainly metabolized in the liver, the dosage should be adjusted according to the degree of hepatic function.

PRECAUTIONS RELATING TO EXCIPIENTS

This medicine contains sucrose. Patients with hereditary fructose intolerance, glucose-galactose malabsorption, or sucrase-isomaltase deficiency should not take this medicine.

ADVERSE REACTIONS

The adverse effects of caffeine are generally frequent, although mild and transient. In most cases, adverse reactions are an extension of the pharmacological action and primarily affect the central nervous system. The most characteristic adverse reactions are:

- Frequently (10-25%): [INSOMNIA], [AGITATION] and [EXCITABILITY].

- Occasionally (1-9%): [NAUSEA], [VOMITING], [DIARRHEA], [GASTRALGIA], [HEADACHE], [TINNITUS], [DISORIENTATION], [EXTRASYSTOLE], [PALPITATIONS], [TACHYCARDIA], [CARDIAC ARRHYTHMIA], [IRRITABILITY], [HOT FLASHES], [TACHYPNEA], [POLYURIA]; with high doses: episodes of [ANXIETY].

Treatment should be discontinued immediately if the patient experiences any episodes of dizziness or palpitations.

COMPOSITION

CAFFEINE: 300 MILLIGRAMS
SUCROSE (EXCIPIENT): 59.2 MILLIGRAMS