The sensation of pain or irritation from using a vape cartridge, often called a “throat hit,” results from a complex interaction of chemical properties, device mechanics, and inhalation technique. While some users expect a mild sensation, true pain signals that the throat and respiratory tissues are being physically or chemically stressed. Understanding the specific components at play helps differentiate a normal sensation from genuine discomfort and potential harm. The causes range from the liquid’s base ingredients to unintended contaminants in the final product, making identification crucial.
Chemical and Compositional Irritants
The liquid’s basic makeup contains potential irritants that interact directly with the throat’s mucosal lining. The carrier liquids, propylene glycol (PG) and vegetable glycerin (VG), are major factors in throat feel. Propylene glycol is a thinner liquid known to be a mild irritant; it carries flavor well and produces a sharper, more pronounced hit that many former smokers seek.
Conversely, VG is thicker and smoother, leading to less irritation and a milder sensation. A high PG ratio directly increases the harshness of the vapor, causing dryness and irritation in sensitive users. This effect is amplified because PG is hygroscopic, meaning it actively draws moisture from the mouth and throat tissues, causing dehydration that exacerbates the scratchy feeling.
The concentration and type of the active compound also contribute significantly to harshness. High concentrations of freebase nicotine are chemically harsher on the throat lining due to their higher pH level. Highly potent cannabinoid oils, such as those with high THC or terpene concentrations, can also cause a strong, sometimes painful, burn. Certain artificial flavoring chemicals are documented mucosal irritants, including cinnamaldehyde (cinnamon flavor) and benzaldehyde (almond flavor), which have been shown to be cytotoxic.
The Role of Device Settings and Vaping Technique
Beyond chemical composition, the physics of vaporization and inhalation cause physical and thermal irritation. Setting the device’s wattage or temperature too high is a common cause of discomfort. Excessive power vaporizes the liquid at a much hotter temperature, which can lead to thermal burns or excessive dehydration of the throat tissue.
Inhalation technique compounds this thermal stress. Drawing too hard or too long pulls superheated vapor too quickly into the airways, increasing irritation. If the liquid level is too low, the heating element can scorch the wicking material, resulting in a “dry hit” of extremely hot, acrid vapor that causes immediate and painful burning.
The hygroscopic nature of PG requires constant hydration to mitigate its drying effects. Frequent use without adequate water intake leads to systemic dehydration, leaving throat tissues vulnerable to irritation. Adjusting the device’s airflow also influences vapor temperature; a restricted draw concentrates heat and intensifies the throat hit, while a wider airflow helps cool the vapor.
Identifying Potential Product Quality Issues
The most severe throat and lung pain is often linked to product quality issues, particularly from unregulated or illicit cartridges. Heating elements, typically coils made of metal alloys, can shed tiny particles when heated. Studies show that toxic heavy metals, including lead, nickel, chromium, and manganese, can leach from the coil and be inhaled in the aerosol.
Inhaling these metal particulates causes acute irritation and poses a long-term respiratory risk. The presence of cutting agents or thickeners in the oil is another serious concern, especially in black-market products. Vitamin E Acetate (VEA) was historically used as a diluent in illicit THC cartridges because it mimics the viscosity of pure oil.
When inhaled, VEA does not vaporize properly and instead coats the lung lining, which was a primary cause of the severe lung illness known as EVALI. Furthermore, residues from cannabis cultivation, such as pesticides, can become highly concentrated in the final oil. Toxins like the fungicide myclobutanil break down into noxious compounds, including hydrogen cyanide, when heated, leading to toxic inhalation and severe discomfort.
Strategies for Reducing Throat Discomfort
Minimizing throat irritation requires adjusting both the product and usage technique. A primary strategy is to switch the liquid composition by selecting cartridges with a higher VG to PG ratio (70% VG or higher) to reduce PG’s irritating and drying effects. Choosing a lower concentration of nicotine or switching to a smoother nicotine salt formulation can also lessen chemical harshness.
Adjusting Device and Technique
Users should examine their device settings and vaping habits. Lowering the device’s wattage or temperature setting prevents the vapor from becoming excessively hot and thermally irritating the throat. Taking shorter, gentler puffs and ensuring the cartridge is sufficiently filled avoids dry hits and prevents inhaling scorched wicking material.
Hydration and Medical Attention
Consistent hydration is an effective preventative measure because PG is a dehydrating agent. Drinking plenty of water helps replenish moisture lost from the throat and mouth tissues. If irritation is severe, persistent, or accompanied by symptoms like chest pain or shortness of breath, discontinue use immediately and seek medical attention, as this may indicate a serious quality issue or contamination.