drug test * drug testing * employee drug testing * urine test * marijuana drug test * urine drug test * hair drug test * drug test * drug test kit * saliva drug test * panel drug testing

Drug Classification

 Depressants

In medicine, a drug or other agent that slows the activity of vital organs of the body. Depressants acting on the central nervous system include general anesthetics, opiates, alcohol, and hypnotics. Tranquilizing drugs (ataractics) act primarily on the lower levels of the brain, relieving tension without reducing mental sharpness.

Chloral Hydrate

Barbiturates
 

Benzodiazepines

Glutethimide

Narcotics

The narcotic analgesics act primarily on the CNS. The perception of and emotional response to pain is modified when the narcotic analgesics bind with stereospecific receptors in the CNS. Five major groups of opioid receptors are known: mu, kappa, sigma, delta and epsilon. Narcotic analgesic activity occurs at the mu, kappa and sigma receptors. Opioid agonists such as morphine and others exert their activity mainly at the mu receptor. Mixed agonist-antagonists such as butorphanol, nalbuphine and pentazocine act primarily at the kappa receptors (thought to mediate analgesic effects) and sigma receptors (may produce subjective and psychotomimetic effects).

As well as analgesia, opioid agonist activity in the CNS causes suppression of the cough reflex, change in mood such as euphoria or dysphoria, mental clouding and EEG changes. Nausea and vomiting, probably caused by stimulation of the chemoreceptor trigger zone, can also occur. Peripheral vasodilation, reduced peripheral resistance and the inhibition of baroreceptors can result in orthostatic hypotension and fainting. The inhibition of peristalsis can lead to constipation while increased bladder sphincter tone may cause urinary retention.

Large doses may elicit excitation or seizures. Morphine and its congeners cause miosis. In therapeutic doses they increase accommodation and sensitivity to light reflex and decrease intraocular pressure in both normal patients and those with glaucoma.                                    

Stimulants

Any drug that excites any bodily function, but more specifically those that stimulate the brain and central nervous system. Stimulants induce alertness, elevated mood, wakefulness, increased speech and motor activity and decrease appetite. Their therapeutic use is limited, but their mood-elevating effects make some of them potent drugs of abuse.
The major stimulant drugs are amphetamines and related compounds, methylxanthines (methylated purines), cocaine, and nicotine.

Amphetamines achieve their effect by increasing the amount and activity of the neurotransmitter norepinephrine (noradrenaline) within the brain. They facilitate the release of norepinephrine by nerve cells and interfere with the cells' reuptake and breakdown of the chemical, thereby increasing its availability within the brain. The most commonly used amphetamines are methamphetamine (Methedrine), amphetamine sulfate (Benzedrine), and dextroamphetamine sulfate (Dexedrine). Amphetamines were first used in the 1930s to treat narcolepsy and subsequently became prescribed for obesity and fatigue.

Their heavy or prolonged use causes irritability, restlessness, hyperactivity, anxiety, excessive speech, and rapid mood swings. Still higher doses or chronic use can cause agitation, tremor, confusion, and, in the most serious cases, a state resembling paranoid schizophrenia. Moreover, letdown effects of deep depression and physical exhaustion may occur after only a single dose of moderate strength wears off. With repeated use, tolerance develops, so that a user needs to take larger doses, but the accompanying dependence is not strong enough to be termed a physical addiction. Amphetamines are widely abused, in some cases by workers or students seeking enhanced physical energy and mental acuity to fulfill demanding tasks.

Certain drugs related to the amphetamines have the same mode of action but are somewhat milder stimulants. Among them are phenmetrazine (Preludin) and methylphenidate (Ritalin). The latter drug is widely used to “slow down” hyperactive children and improve their ability to concentrate.

The methylxanthines are even milder stimulants. Unlike the amphetamines and methylphenidate, which are synthetically manufactured, these compounds occur naturally in various plants and have been used by humans for many centuries. The most important of them are caffeine, theophylline, and theobromine. The strongest is caffeine, which is the active ingredient of coffee, tea, cola beverages, and maté. Theobromine is the active ingredient in cocoa. Caffeine constricts blood vessels of the brain; for this reason it is often a component of headache remedies. Theophylline is used in the treatment of severe asthma because of its capacity for relaxing the bronchioles in the lungs.

Cocaine is one of the strongest and shortest-acting stimulants and has a high potential for abuse owing to its euphoric and habit-forming effects. Nicotine, the active ingredient in cigarettes and other tobacco products, may also be regarded as a stimulant.                                   

Hallucinogins

Hallucinogenic drugs are substances that distort the perception of objective reality. The most well-known hallucinogens include phencyclidine, otherwise known as PCP, angel dust, or loveboat; lysergic acid diethylamide, commonly known as LSD or acid; mescaline and peyote; and psilocybin, or "magic" mushrooms. Under the influence of hallucinogens, the senses of direction, distance, and time become disoriented.

These drugs can produce unpredictable, erratic, and violent behavior in users that sometimes leads to serious injuries and death. The effect of hallucinogens can last for 12 hours.
 

LSD produces tolerance, so that users who take the drug repeatedly must take higher and higher doses in order to achieve the same state of intoxication. This is extremely dangerous, given the unpredictability of the drug, and can result in increased risk of convulsions, coma, heart and lung failure, and even death.