Physiological Mechanisms of Appetite Regulation
Feeding behavior is regulated by the hypothalamus, which contains two interconnected centers: the hunger center and the satiety center.
Neurotransmitter regulation plays a crucial role:
- Noradrenergic transmission: stimulation of this pathway inhibits the hunger center.
- Serotonergic transmission: stimulation activates the satiety center.
Impairments in these pathways serve as targets for pharmacological intervention.
Classification of Appetite-Regulating Drugs
Modern pharmacology identifies two main groups of agents that purposefully alter feeding behavior:
- Appetite stimulants — used for decreased appetite or loss of appetite to activate digestive processes.
- Appetite suppressants (anorectic agents) — used for the management of excess body weight.
Bitters (Amara) and Herbal Materials
The group of appetite stimulants is compositionally divided into bitters (Amara) and preparations containing essential oils.
Herbal materials of the Amara group include:
- Sweet flag rhizome (Rhizomata Calami);
- Dandelion root (Radix Taraxaci);
- Wormwood herb (Herba Absinthii).
The active constituents here are glycosides, which possess a specific bitter taste.
Mechanism of Action and Pharmacodynamics of Bitters
According to classic physiological principles, the mechanism of action of bitters is as follows:
- Stimulation of taste receptors located on the oral mucosa.
- Reflex enhancement of digestive gland secretion.
Pharmacodynamic features:
- The effect manifests exclusively during food intake, as meal-associated secretion is specifically stimulated.
- The principle of action is analogous to traditional aperitifs.
- The drugs must be taken 15–20 minutes before the start of a meal.
Essential Oil-Containing Preparations
In addition to pure bitters, complex herbal preparations are used to stimulate appetite. A prominent example is the combined agent Altalex based on diluted ethanol.
It contains a complex mixture of essential oils: peppermint, Melissa, fennel, nutmeg, clove, thyme, pine needle, anise, sage, cinnamon, and lavender.
Pharmacological effects of the drug:
- Stimulation of appetite and gastric juice secretion;
- Choleretic action;
- Spasmolytic action;
- Sedative effect.