5-hydroxytryptamine receptors or 5-HT receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in the central and peripheral nervous systems. They mediate both inhibitory neurotransmission; the serotonin receptors are activated by the neurotransmitter serotonin, which acts as their natural ligand. The serotonin receptors modulate the release of many neurotransmitters, including glutamate, GABA, epinephrine / norepinephrine, acetylcholine, as well as many hormones, including oxytocin, vasopressin, cortisol and substance P, among others; the serotonin receptors influence various biological and neurological processes such as aggression, appetite, learning, mood, nausea and thermoregulation. The serotonin receptors are the target of a variety of pharmaceutical and recreational drugs, including many antidepressants, anorectics, gastroprokinetic agents, antimigraine agents and entactogens. Serotonin receptors are found in all animals and are known to regulate longevity and behavioral aging in the primitive nematode, Caenorhabditis elegans.
5-hydroxytryptamine receptors or 5-HT receptors, or serotonin receptors are found in the central and peripheral nervous systems. They can be divided into 7 families of G protein-coupled receptors except for the 5-HT3 receptor, a ligand-gated ion channel, which activate an intracellular second messenger cascade to produce an excitatory or inhibitory response. In 2014, a novel 5-HT receptor was isolated from the small white butterfly, Pieris rapae, named pr5-HT8, it does not occur in mammals and shares low similarity to the known 5-HT receptor classes. The 7 general serotonin receptor classes include a total of 14 known serotonin receptors; the specific types have been characterized as follows: Note that there is no 5-HT1C receptor since, after the receptor was cloned and further characterized, it was found to have more in common with the 5-HT2 family of receptors and was redesignated as the 5-HT2C receptor. Nonselective agonists of 5-HT receptor subtypes include ergotamine, which activates 5-HT1A, 5-HT1D, 5-HT1B, D2 and norepinephrine receptors.
LSD is a 5-HT2A, 5-HT2C, 5-HT5A, 5-HT5, 5-HT6 agonist. The genes coding for serotonin receptors are expressed across the mammalian brain. Genes coding for different receptors types follow different developmental curves. There is a developmental increase of HTR5A expression in several subregions of the human cortex, paralleled by a decreased expression of HTR1A from the embryonic period to the post-natal one. A number of receptors were classed as "5-HT1-like" - by 1998 it was being argued that, since these receptors were "a heterogeneous population of 5-HT1B, 5-HT1D and 5-HT7" receptors the classification was redundant. Serotonin+Receptors at the US National Library of Medicine Medical Subject Headings "5-Hydroxytryptamine Receptors". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Rubenstein LA, Lanzara RG. "Activation of G protein-coupled receptors entails cysteine modulation of agonist binding". Cogprints. Retrieved 2008-04-11. Paterson LM, Kornum BR, Nutt DJ, Pike VW, Knudsen GM.
"5-HT radioligands for human brain imaging with PET and SPECT". Med Res Rev. 33: 54–111. Doi:10.1002/med.20245. PMC 4188513. PMID 21674551
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. They are sometimes called blockers. In pharmacology, antagonists have affinity but no efficacy for their cognate receptors, binding will disrupt the interaction and inhibit the function of an agonist or inverse agonist at receptors. Antagonists mediate their effects by binding to the active site or to the allosteric site on a receptor, or they may interact at unique binding sites not involved in the biological regulation of the receptor's activity. Antagonist activity may be reversible or irreversible depending on the longevity of the antagonist–receptor complex, which, in turn, depends on the nature of antagonist–receptor binding; the majority of drug antagonists achieve their potency by competing with endogenous ligands or substrates at structurally defined binding sites on receptors. The English word antagonist in pharmaceutical terms comes from the Greek ἀνταγωνιστής – antagonistēs, "opponent, villain, rival", derived from anti- and agonizesthai.
Biochemical receptors are large protein molecules that can be activated by the binding of a ligand such as a hormone or a drug. Receptors can be membrane-bound, as cell surface receptors, or inside the cell as intracellular receptors, such as nuclear receptors including those of the mitochondrion. Binding occurs as a result of non-covalent interactions between the receptor and its ligand, at locations called the binding site on the receptor. A receptor may contain one or more binding sites for different ligands. Binding to the active site on the receptor regulates receptor activation directly; the activity of receptors can be regulated by the binding of a ligand to other sites on the receptor, as in allosteric binding sites. Antagonists mediate their effects through receptor interactions by preventing agonist-induced responses; this may be accomplished by binding to the allosteric site. In addition, antagonists may interact at unique binding sites not involved in the biological regulation of the receptor's activity to exert their effects.
The term antagonist was coined to describe different profiles of drug effects. The biochemical definition of a receptor antagonist was introduced by Ariens and Stephenson in the 1950s; the current accepted definition of receptor antagonist is based on the receptor occupancy model. It narrows the definition of antagonism to consider only those compounds with opposing activities at a single receptor. Agonists were thought to turn "on" a single cellular response by binding to the receptor, thus initiating a biochemical mechanism for change within a cell. Antagonists were thought to turn "off" that response by'blocking' the receptor from the agonist; this definition remains in use for physiological antagonists, substances that have opposing physiological actions, but act at different receptors. For example, histamine lowers arterial pressure through vasodilation at the histamine H1 receptor, while adrenaline raises arterial pressure through vasoconstriction mediated by alpha-adrenergic receptor activation.
Our understanding of the mechanism of drug-induced receptor activation and receptor theory and the biochemical definition of a receptor antagonist continues to evolve. The two-state model of receptor activation has given way to multistate models with intermediate conformational states; the discovery of functional selectivity and that ligand-specific receptor conformations occur and can affect interaction of receptors with different second messenger systems may mean that drugs can be designed to activate some of the downstream functions of a receptor but not others. This means efficacy may depend on where that receptor is expressed, altering the view that efficacy at a receptor is receptor-independent property of a drug. By definition, antagonists display no efficacy to activate the receptors they bind. Antagonists do not maintain the ability to activate a receptor. Once bound, antagonists inhibit the function of agonists, inverse agonists, partial agonists. In functional antagonist assays, a dose-response curve measures the effect of the ability of a range of concentrations of antagonists to reverse the activity of an agonist.
The potency of an antagonist is defined by its half maximal inhibitory concentration. This can be calculated for a given antagonist by determining the concentration of antagonist needed to elicit half inhibition of the maximum biological response of an agonist. Elucidating an IC50 value is useful for comparing the potency of drugs with similar efficacies, however the dose-response curves produced by both drug antagonists must be similar; the lower the IC50 the greater the potency of the antagonist, the lower the concentration of drug, required to inhibit the maximum biological response. Lower concentrations of drugs may be associated with fewer side-effects; the affinity of an antagonist for its binding site, i.e. its ability to bind to a receptor, will determine the duration of inhibition of agonist activity. The affinity of an antagonist can be determined experimentally using Schild regression or for competitive antagonists in radioligand binding studies using the Cheng-Prusoff equation. Schild regression can be used to determine the nature of antagonism as beginning either competitive or non-competitive and Ki determination is independent of the affinity, efficacy or concentration of the agonist used.
However, it is important. The effects of receptor desensitization on reaching equilibrium must als
Dopamine is an organic chemical of the catecholamine and phenethylamine families. It functions both as a hormone and a neurotransmitter, plays several important roles in the brain and body, it is an amine synthesized by removing a carboxyl group from a molecule of its precursor chemical L-DOPA, synthesized in the brain and kidneys. Dopamine is synthesized in plants and most animals. In the brain, dopamine functions as a neurotransmitter—a chemical released by neurons to send signals to other nerve cells; the brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior. The anticipation of most types of rewards increases the level of dopamine in the brain, many addictive drugs increase dopamine release or block its reuptake into neurons following release. Other brain dopamine pathways are involved in motor control and in controlling the release of various hormones; these pathways and cell groups form a dopamine system, neuromodulatory.
In popular culture and media, dopamine is seen as the main chemical of pleasure, but the current opinion in pharmacology is that dopamine instead confers motivational salience. Outside the central nervous system, dopamine functions as a local paracrine messenger. In blood vessels, it acts as a vasodilator. With the exception of the blood vessels, dopamine in each of these peripheral systems is synthesized locally and exerts its effects near the cells that release it. Several important diseases of the nervous system are associated with dysfunctions of the dopamine system, some of the key medications used to treat them work by altering the effects of dopamine. Parkinson's disease, a degenerative condition causing tremor and motor impairment, is caused by a loss of dopamine-secreting neurons in an area of the midbrain called the substantia nigra, its metabolic precursor L-DOPA can be manufactured. There is evidence that schizophrenia involves altered levels of dopamine activity, most antipsychotic drugs used to treat this are dopamine antagonists which reduce dopamine activity.
Similar dopamine antagonist drugs are some of the most effective anti-nausea agents. Restless legs syndrome and attention deficit hyperactivity disorder are associated with decreased dopamine activity. Dopaminergic stimulants can be addictive in high doses, but some are used at lower doses to treat ADHD. Dopamine itself is available as a manufactured medication for intravenous injection: although it cannot reach the brain from the bloodstream, its peripheral effects make it useful in the treatment of heart failure or shock in newborn babies. A dopamine molecule consists of a catechol structure with one amine group attached via an ethyl chain; as such, dopamine is the simplest possible catecholamine, a family that includes the neurotransmitters norepinephrine and epinephrine. The presence of a benzene ring with this amine attachment makes it a substituted phenethylamine, a family that includes numerous psychoactive drugs. Like most amines, dopamine is an organic base; as a base, it is protonated in acidic environments.
The protonated form is water-soluble and stable, but can become oxidized if exposed to oxygen or other oxidants. In basic environments, dopamine is not protonated. In this free base form, it is less water-soluble and more reactive; because of the increased stability and water-solubility of the protonated form, dopamine is supplied for chemical or pharmaceutical use as dopamine hydrochloride—that is, the hydrochloride salt, created when dopamine is combined with hydrochloric acid. In dry form, dopamine hydrochloride is a fine colorless powder. Dopamine is synthesized in a restricted set of cell types neurons and cells in the medulla of the adrenal glands; the primary and minor metabolic pathways are: Primary: L-Phenylalanine → L-Tyrosine → L-DOPA → Dopamine Minor: L-Phenylalanine → L-Tyrosine → p-Tyramine → Dopamine Minor: L-Phenylalanine → m-Tyrosine → m-Tyramine → DopamineThe direct precursor of dopamine, L-DOPA, can be synthesized indirectly from the essential amino acid phenylalanine or directly from the non-essential amino acid tyrosine.
These amino acids are found in nearly every protein and so are available in food, with tyrosine being the most common. Although dopamine is found in many types of food, it is incapable of crossing the blood–brain barrier that surrounds and protects the brain, it must therefore be synthesized inside the brain to perform its neuronal activity. L-Phenylalanine is converted into L-tyrosine by the enzyme phenylalanine hydroxylase, with molecular oxygen and tetrahydrobiopterin as cofactors. L-Tyrosine is converted into L-DOPA by the enzyme tyrosine hydroxylase, with tetrahydrobiopterin, O2, iron as cofactors. L-DOPA is converted into dopamine by the enzyme aromatic L-amino acid decarboxylase, with pyridoxal phosphate as the cofactor. Dopamine itself is used as precursor in the synthesis o
The 5-HT3 receptor belongs to the Cys-loop superfamily of ligand-gated ion channels and therefore differs structurally and functionally from all other 5-HT receptors receptors which are G protein-coupled receptors. This ion channel is cation-selective and mediates neuronal depolarization and excitation within the central and peripheral nervous systems; as with other ligand gated ion channels, the 5-HT3 receptor consists of five subunits arranged around a central ion conducting pore, permeable to sodium and calcium ions. Binding of the neurotransmitter 5-hydroxytryptamine to the 5-HT3 receptor opens the channel, which, in turn, leads to an excitatory response in neurons; the activating, inward current is predominantly carried by sodium and potassium ions. 5-HT3 receptors have a negligible permeability to anions. They are most related by homology to the nicotinic acetylcholine receptor; the 5-HT3 receptor differs markedly in structure and mechanism from the other 5-HT receptor subtypes, which are all G-protein-coupled.
A functional channel may be composed of five identical 5-HT3A subunits or a mixture of 5-HT3A and one of the other four 5-HT3B, 5-HT3C, 5-HT3D, or 5-HT3E subunits. It appears. All other subunit subtypes must heteropentamerize with 5-HT3A subunits to form functional channels. Additionally, there has not been any pharmacological difference found between the heteromeric 5-HT3AC, 5-HT3AD, 5-HT3AE, the homomeric 5-HT3A receptor. N-terminal glycosylation of receptor subunits is critical for subunit assembly and plasma membrane trafficking; the subunits surround a central ion channel in a pseudo-symmetric manner. Each subunit comprises an extracellular N-terminal domain which comprises the orthosteric ligand-binding site. Whereas extracellular domain is the site of action of agonists and competitive antagonists, the transmembrane domain contains the central ion pore, receptor gate, principle selectivity filter that allows ions to cross the cell membrane; the 5-HT3 receptor gene is located on human chromosomal region 11q23.1-q23.2.
It is similar in structure to the mouse gene, spread over ~ 13 kb. Four of its introns are in the same position as the introns in the homologous α7-acetylcholine receptor gene proving their evolutionary relationship. Additional genes that code for the subunits of the 5-HT3 receptor have been identified. HTR3A and HTR3B for the 5-HT3A and 5-HT3B subunits and in addition HTR3C, HTR3D and HTR3E genes encoding 5-HT3C, 5-HT3D and 5-HT3E subunits. HTR3C and HTR3E do not seem to form functional homomeric channels, but when co-expressed with HTR3A they form heteromeric complex with decreased or increased 5-HT efficacies; the pathophysiological role for these additional subunits has yet to be identified. Expression; the 5-HT3C, 5-HT3D and 5-HT3E genes tend to show peripherally restricted pattern of expression, with high levels in the gut. In human duodenum and stomach, for example, 5-HT3C and 5-HT3E mRNA might be greater than for 5-HT3A and 5-HT3B. Polymorphism. In patients treated with chemotherapeutic drugs, certain polymorphism of the HTR3B gene could predict successful antiemetic treatment.
This could indicate that the 5-HTR3B receptor subunit could be used as biomarker of antiemetic drug efficacy. The 5-HT3 receptor is expressed throughout the central and peripheral nervous systems and mediates a variety of physiological functions. On a cellular level, it has been shown that postsynaptic 5-HT3 receptors mediate fast excitatory synaptic transmission in rat neocortical interneurons and hippocampus, in ferret visual cortex. 5-HT3 receptors are present on presynaptic nerve terminals. There is some evidence for a role in modulation of neurotransmitter release, but evidence is inconclusive; when the receptor is activated to open the ion channel by agonists, the following effects are observed: CNS: nausea and vomiting center in brain stem, seizure propensity, pro-nociception PNS: neuronal excitation, emesis Agonists for the receptor include: Cereulide 2-methyl-5-HT Alpha-Methyltryptamine Bufotenin Chlorophenylbiguanide Ethanol Ibogaine Phenylbiguanide Quipazine RS-56812: Potent and selective 5-HT3 partial agonist, 1000x selectivity over other serotonin receptors SR-57227 Varenicline YM-31636 Antagonists for the receptor include: Antiemetics AS-8112 Granisetron Ondansetron Tropisetron Gastroprokinetics Alosetron Batanopride Metoclopramide Renzapride Zacopride M1, the major active metabolite of mosapride Antidepressants Mianserin Mirtazapine Vortioxetine Antipsychotics Clozapine Olanzapine Quetiapine Antimalarials Quinine Chloroquine Mefloquine Others 3-Tropanyl indole-3-carboxylate Lamotrigine Memantine Menthol Thujone These agents are not agonists at the receptor, but increase the affinity or efficacy of the receptors for an agonist: Indole Derivatives 5-chloroindole Small Organic Anaesthetics Ethanol Chloroform Halothane Isoflurane Identification of the 5-HT3 receptor did not take place until 1986 because of a lack of selective pharmacological tool.
However, with the discovery that the 5-HT3 receptor plays a prominent role in chemotherapy- and radiotherapy-induced vomiting, the conc
Clinical trials are experiments or observations done in clinical research. Such prospective biomedical or behavioral research studies on human participants are designed to answer specific questions about biomedical or behavioral interventions, including new treatments and known interventions that warrant further study and comparison. Clinical trials generate data on efficacy, they are conducted only after they have received health authority/ethics committee approval in the country where approval of the therapy is sought. These authorities are responsible for vetting the risk/benefit ratio of the trial – their approval does not mean that the therapy is'safe' or effective, only that the trial may be conducted. Depending on product type and development stage, investigators enroll volunteers or patients into small pilot studies, subsequently conduct progressively larger scale comparative studies. Clinical trials can vary in size and cost, they can involve a single research center or multiple centers, in one country or in multiple countries.
Clinical study design aims to ensure the scientific reproducibility of the results. Costs for clinical trials can range into the billions of dollars per approved drug; the sponsor may be a governmental organization or a pharmaceutical, biotechnology or medical device company. Certain functions necessary to the trial, such as monitoring and lab work, may be managed by an outsourced partner, such as a contract research organization or a central laboratory. Only 10 percent of all drugs started in human clinical trials become an approved drug; some clinical trials involve healthy subjects with no pre-existing medical conditions. Other clinical trials pertain to patients with specific health conditions who are willing to try an experimental treatment; when participants are healthy volunteers who receive financial incentives, the goals are different than when the participants are sick. During dosing periods, study subjects remain under supervision for one to 40 nights. Pilot experiments are conducted to gain insights for design of the clinical trial to follow.
There are two goals to testing medical treatments: to learn whether they work well enough, called "efficacy" or "effectiveness". Neither is an absolute criterion; the benefits must outweigh the risks. For example, many drugs to treat cancer have severe side effects that would not be acceptable for an over-the-counter pain medication, yet the cancer drugs have been approved since they are used under a physician's care, are used for a life-threatening condition. In the US, the elderly constitute 14 % of the population. People over 55 are excluded from trials because their greater health issues and drug use complicate data interpretation, because they have different physiological capacity than younger people. Children and people with unrelated medical conditions are frequently excluded. Pregnant women are excluded due to potential risks to the fetus; the sponsor designs the trial in coordination with a panel of expert clinical investigators, including what alternative or existing treatments to compare to the new drug and what type of patients might benefit.
If the sponsor cannot obtain enough test subjects at one location investigators at other locations are recruited to join the study. During the trial, investigators recruit subjects with the predetermined characteristics, administer the treatment and collect data on the subjects' health for a defined time period. Data include measurements such as vital signs, concentration of the study drug in the blood or tissues, changes to symptoms, whether improvement or worsening of the condition targeted by the study drug occurs; the researchers send the data to the trial sponsor, who analyzes the pooled data using statistical tests. Examples of clinical trial goals include assessing the safety and relative effectiveness of a medication or device: On a specific kind of patient, for example, a patient, diagnosed with Alzheimer's disease At varying dosages, for example, a 10 milligram dose instead of a 5 milligram dose For a new indication Evaluation for improved efficacy in treating a patient's condition as compared to the standard therapy for that condition Evaluation of the study drug or device relative to two or more approved/common interventions for that condition, for example, device A versus device B, or therapy A versus therapy B)While most clinical trials test one alternative to the novel intervention, some expand to three or four and may include a placebo.
Except for small, single-location trials, the design and objectives are specified in a document called a clinical trial protocol. The protocol is the trial's "operating manual" and ensures that all researchers perform the trial in the same way on similar subjects and that the data is comparable across all subjects; as a trial is designed to test hypotheses and rigorously monitor and assess outcomes, it can be seen as an application of the scientific method the experimental step. The most common clinical trials evaluate new pharmaceutical products, medical devices, psychological therapies, or other interventions. Clinical trials may be required before a national regulatory authority approves marketing of the innovation. To drugs, manufacturers of medical devices in the United States are required to conduct clinical trials for premarket appr
Cannabidiol is a phytocannabinoid discovered in 1940. It is one of some 113 identified cannabinoids in cannabis plants, accounting for up to 40% of the plant's extract; as of 2018, preliminary clinical research on cannabidiol included studies of anxiety, movement disorders, pain. Cannabidiol can be taken into the body in multiple ways, including by inhalation of cannabis smoke or vapor, as an aerosol spray into the cheek, by mouth, it may be supplied as CBD oil containing only CBD as the active ingredient, a full-plant CBD-dominant hemp extract oil, dried cannabis, or as a prescription liquid solution. CBD does not have the same psychoactivity as THC, may affect the actions of THC. Although in vitro studies indicate CBD may interact with different biological targets, including cannabinoid receptors and other neurotransmitter receptors, as of 2018 the mechanism of action for its biological effects has not been determined. In the United States, the cannabidiol drug Epidiolex has been approved by the Food and Drug Administration for treatment of two epilepsy disorders.
The side effects of long-term use of the drug include somnolence, decreased appetite, fatigue, weakness, sleeping problems. The U. S. Drug Enforcement Administration has assigned Epidiolex a Schedule V classification, while non-Epidiolex CBD remains a Schedule I drug prohibited for any use. Cannabidiol is not scheduled under any United Nations drug control treaties, in 2018 the World Health Organization recommended that it remain unscheduled. There has been little high-quality research into the use of cannabidiol for epilepsy, what there is is limited to refractory epilepsy in children. While the results of using medical-grade cannabidiol in combination with conventional medication shows some promise, they did not lead to seizures being eliminated, were associated with some minor adverse effects. An orally administered cannabidiol solution was approved by the US Food and Drug Administration in June 2018 as a treatment for two rare forms of childhood epilepsy, Lennox-Gastaut syndrome and Dravet syndrome.
Preliminary research on other possible therapeutic uses for cannabidiol include several neurological disorders, but the findings have not been confirmed by sufficient high-quality clinical research to establish such uses in clinical practice. Preliminary research indicates that cannabidiol may reduce adverse effects of THC those causing intoxication and sedation, but only at high doses. Safety studies of cannabidiol showed it is well-tolerated, but may cause tiredness, diarrhea, or changes in appetite as common adverse effects. Epidiolex documentation lists sleepiness and poor quality sleep, decreased appetite and fatigue. Laboratory evidence indicated that cannabidiol may reduce THC clearance, increasing plasma concentrations which may raise THC availability to receptors and enhance its effect in a dose-dependent manner. In vitro, cannabidiol inhibited receptors affecting the activity of voltage-dependent sodium and potassium channels, which may affect neural activity. A small clinical trial reported that CBD inhibited the CYP2C-catalyzed hydroxylation of THC to 11-OH-THC.
Little is known about potential drug interactions but CBD-mediates decrease in clobazam metabolism. Cannabidiol has low affinity for the cannabinoid CB2 receptors. Cannabidiol may be an antagonist of GPR55, a G protein-coupled receptor and putative cannabinoid receptor, expressed in the caudate nucleus and putamen in the brain, it may act as an inverse agonist of GPR3, GPR6, GPR12. CBD has been shown to act as a serotonin 5-HT1A receptor partial agonist, this action may be involved in its antidepressant and neuroprotective effects, it is an allosteric modulator of the μ- and δ-opioid receptors as well. The pharmacological effects of CBD may involve PPARγ intracellular calcium release; the oral bioavailability of CBD is 13 to 19%, while its bioavailability via inhalation is 11 to 45%. The elimination half-life of CBD is 18–32 hours. Cannabidiol is metabolized in the liver as well as in the intestines by CYP2C19 and CYP3A4 enzymes, UGT1A7, UGT1A9, UGT2B7 isoforms. CBD may have a wide margin in dosing.
Nabiximols is a patented medicine containing THC in equal proportions. The drug was approved by Health Canada in 2005 for prescription to treat central neuropathic pain in multiple sclerosis, in 2007 for cancer related pain. In New Zealand, Sativex is "approved for use as an add-on treatment for symptom improvement in people with moderate to severe spasticity due to multiple sclerosis who have not responded adequately to other anti-spasticity medication." Cannabidiol is soluble in organic solvents such as pentane. At room temperature, it is a colorless crystalline solid. In basic media and the presence of air, it is oxidized to a quinone. Under acidic conditions it cyclizes to THC, which occurs during pyrolysis; the synthesis of cannabidiol has been accomplished by several research groups. Cannabis produces CBD-carboxylic acid through the same metabolic pathway as THC, until the next to last step, where CBDA synthase performs catalysis instead of THCA synthase. Cannabinoids were isolated from the cannabis plant in 1940 by Roger Adams, its chemical structure was established in 1963.
Cannabidiol is the generic name of the drug and its INN. Food and beverage products containing CBD were introduced in the United States in 2017. Similar to energy drinks and protein bars which may contain vitamin or herbal additives and beverage items can be infused with CBD as an alternative means of ingesting the substance. In the United S