Usage
Cyproheptadine + Lysine is a combination medication primarily used as an appetite stimulant and nutritional supplement. It is prescribed for conditions such as:
- Loss of appetite and unintentional weight loss
- Anorexia nervosa (eating disorder characterized by significantly low body weight)
- Malnutrition or failure to thrive (especially in children)
- Weight loss due to chronic illnesses (e.g., cancer, HIV/AIDS)
- Countering appetite suppression caused by certain medications
Pharmacological Classification:
- Cyproheptadine: Antihistamine, antiserotonergic
- Lysine: Essential amino acid, nutritional supplement
Mechanism of Action:
Cyproheptadine acts as an antagonist at histamine H1 receptors and serotonin 5-HT2 receptors in the hypothalamus, a region of the brain that regulates appetite. This antagonism leads to increased appetite. Lysine, an essential amino acid, contributes to protein synthesis and aids in overall growth and development, supporting the weight gain facilitated by Cyproheptadine.
Alternate Names
While Cyproheptadine + Lysine doesn’t have a specific international nonproprietary name (INN), the individual components do:
- Cyproheptadine: Cyproheptadine hydrochloride
- Lysine: L-Lysine
Brand Names:
Numerous brand names exist depending on the region and specific formulation, which often includes additional vitamins and minerals. Apetatrust, Trimetabol, and various other formulations are available. Periactin is a brand name for Cyproheptadine alone.
How It Works
Pharmacodynamics:
Cyproheptadine exerts its appetite-stimulating effects by blocking the action of histamine and serotonin in the hypothalamus. It also possesses anticholinergic properties, resulting in side effects such as dry mouth, blurred vision, and constipation. Lysine contributes to protein synthesis, supporting the anabolic processes required for weight gain.
Pharmacokinetics:
- Absorption: Cyproheptadine is well-absorbed orally.
- Metabolism: Primarily metabolized in the liver.
- Elimination: Excreted primarily in urine, some in feces.
Mode of Action:
Cyproheptadine acts as a competitive antagonist at H1 and 5-HT2 receptors, preventing the binding of histamine and serotonin. This, in turn, influences the appetite centers within the hypothalamus. Lysine’s primary function is related to protein synthesis and supporting overall nutritional status.
Receptor Binding, Enzyme Inhibition, or Neurotransmitter Modulation:
- Cyproheptadine: H1 and 5-HT2 receptor antagonist.
Elimination Pathways:
Cyproheptadine is metabolized in the liver and excreted primarily through the kidneys.
Dosage
Standard Dosage
Adults:
The typical starting dose is 4 mg three times a day, which can be adjusted based on the patient’s response and tolerance. The maximum daily dose should not exceed 0.5 mg/kg/day or 32 mg/day. Some patients may require doses up to 32mg/day.
Children:
Dosing in children is weight-based and should be carefully determined by a physician. Usual pediatric doses range from 2mg twice a day to 4mg three times a day depending on the age group. Children under 2 should not use the medication.
Special Cases:
- Elderly Patients: Lower starting doses and careful monitoring are recommended due to potential age-related decreases in drug clearance and increased sensitivity to side effects. A starting dose of 4mg twice daily is recommended.
- Patients with Renal Impairment: Dose adjustments and close monitoring are essential.
- Patients with Hepatic Dysfunction: Caution and potential dose modifications are necessary due to liver metabolism.
- Patients with Comorbid Conditions: Careful assessment and individualized dosing are necessary, especially for patients with asthma, glaucoma, hypertension, hyperthyroidism, or urinary retention.
Clinical Use Cases
Cyproheptadine + Lysine is not typically used in clinical settings like intubation, surgical procedures, mechanical ventilation, or the ICU. It is primarily used for nutritional support and appetite stimulation in outpatients.
Dosage Adjustments
Dose modifications are crucial for patients with renal or hepatic dysfunction. The presence of other medical conditions or concomitant medications also necessitates careful dose adjustments based on individual patient needs and potential drug interactions.
Side Effects
Common Side Effects:
- Drowsiness
- Dizziness
- Dry mouth
- Blurred vision
- Constipation
- Increased appetite
Rare but Serious Side Effects:
- Confusion
- Hallucinations
- Difficulty urinating
- Tremors
- Seizures
- Allergic reactions (rash, itching, swelling)
Long-Term Effects:
Chronic use may lead to weight gain and potential metabolic consequences if dietary intake is not carefully managed.
Adverse Drug Reactions (ADR):
Serious ADRs include seizures, severe allergic reactions, and significant cardiovascular effects. These require immediate medical attention.
Contraindications
- Hypersensitivity to cyproheptadine or lysine
- Newborn or premature infants
- Angle-closure glaucoma
- Urinary retention
- Stenosing peptic ulcer
- Pyloroduodenal obstruction
- Concurrent use of MAO inhibitors
Drug Interactions
Cyproheptadine can interact with numerous medications, including:
- CNS depressants (e.g., alcohol, sedatives, tranquilizers)
- Anticholinergics (e.g., antihistamines, tricyclic antidepressants)
- MAO inhibitors
Pregnancy and Breastfeeding
Pregnancy Safety Category: B (Animal studies show no risk, but human studies are limited)
While animal studies haven’t shown fetal harm, human data is insufficient. Cyproheptadine should be used during pregnancy only if clearly needed and the benefit outweighs the risk.
Breastfeeding: Cyproheptadine’s excretion in human milk is unknown, and it is generally advised to avoid its use during breastfeeding due to potential risks to the infant.
Drug Profile Summary
- Mechanism of Action: Cyproheptadine antagonizes H1 and 5-HT2 receptors, stimulating appetite. Lysine aids protein synthesis.
- Side Effects: Drowsiness, dizziness, dry mouth, blurred vision, constipation, increased appetite. Serious side effects are rare but can include seizures and allergic reactions.
- Contraindications: Hypersensitivity, newborns/premature infants, glaucoma, urinary retention, MAOI use.
- Drug Interactions: CNS depressants, anticholinergics, MAO inhibitors.
- Pregnancy & Breastfeeding: Use with caution in pregnancy only if benefit outweighs risk. Avoid during breastfeeding.
- Dosage: Adults: 4mg three times/day, adjustable up to 32 mg/day. Children: Weight-based, consult guidelines.
- Monitoring Parameters: Weight, appetite, side effects, and potential drug interactions.
Popular Combinations
Cyproheptadine + Lysine is often combined with vitamins and minerals to provide comprehensive nutritional support.
Precautions
- Pre-existing conditions: Use cautiously in patients with asthma, glaucoma, hypertension, hyperthyroidism, or urinary retention.
- Pregnant women: Consult physician, use only if benefit outweighs risk.
- Breastfeeding mothers: Avoid.
- Children and elderly: Carefully adjust dose.
- Lifestyle: Avoid alcohol and other CNS depressants. Avoid operating machinery until effects are known.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Cyproheptadine + Lysine?
A: Adults typically start with 4 mg three times a day, adjustable up to 32 mg/day or 0.5mg/kg/day. Pediatric dosing is weight-based and requires careful calculation by a physician.
Q2: What are the most common side effects?
A: Drowsiness, dizziness, dry mouth, blurred vision, and constipation.
Q3: Is Cyproheptadine + Lysine safe during pregnancy?
A: Animal studies show no harm, but human data is limited. Use only if clearly needed and the benefit outweighs the risk. Consult with a physician.
Q4: Can I breastfeed while taking this medication?
A: It’s generally recommended to avoid Cyproheptadine + Lysine during breastfeeding due to unknown risks to the infant.
Q5: What should I do if I miss a dose?
A: Take the missed dose as soon as you remember, unless it’s almost time for your next dose. Do not double up on doses.
Q6: Are there any serious drug interactions I should be aware of?
A: Yes, avoid concomitant use with MAO inhibitors and be cautious with CNS depressants and anticholinergics.
Q7: How does Cyproheptadine + Lysine differ from Cyproheptadine alone?
A: Cyproheptadine + Lysine combines the appetite-stimulating effects of Cyproheptadine with the nutritional benefits of Lysine, promoting both increased appetite and protein synthesis for enhanced weight gain.
Q8: Can Cyproheptadine + Lysine be used for other conditions besides appetite stimulation?
A: Cyproheptadine may be used to treat allergic reactions but the combination with Lysine is primarily indicated for appetite stimulation and nutritional support.
Q9: Can this medication be used long-term?
A: Long-term use is possible, but careful monitoring of weight gain and potential metabolic effects is essential.
