An analgesic drug, also called simply an analgesic, pain reliever, or painkiller, is any member of the group of drugs used for pain management. Analgesics are conceptually distinct from anesthetics, which temporarily reduce, and in some instances eliminate, sensation, although analgesia and anesthesia are neurophysiologically overlapping and thus various drugs have both analgesic and anesthetic effects.
Hydrocodone, also known as dihydrocodeinone, is a semisynthetic opioid used to treat pain and as a cough suppressant. It is taken by mouth. Typically it is dispensed as the combination acetaminophen/hydrocodone or ibuprofen/hydrocodone for pain severe enough to require an opioid and in combination with homatropine methylbromide to relieve cough. It is also available by itself in a long-acting form under the brand name Zohydro ER, among others, to treat severe pain of a prolonged duration. Hydrocodone is a controlled drug: in the United States a Schedule II Controlled Substance.
Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid use disorder. It is used to treat chronic pain, and it is also used to treat addiction to heroin or other opioids. Prescribed for daily use, the medicine relieves cravings and removes withdrawal symptoms. Withdrawal management using methadone can be accomplished in less than a month, or it may be done gradually over a longer period of time, or simply maintained for the rest of the patient's life. While a single dose has a rapid effect, maximum effect can take up to five days of use. After long-term use, in people with normal liver function, effects last 8 to 36 hours. Methadone is usually taken by mouth and rarely by injection into a muscle or vein.
Oxycodone, sold under various brand names such as Roxicodone and OxyContin, is a semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and is a commonly abused drug. It is usually taken by mouth, and is available in immediate-release and controlled-release formulations. Onset of pain relief typically begins within fifteen minutes and lasts for up to six hours with the immediate-release formulation. In the United Kingdom, it is available by injection. Combination products are also available with paracetamol (acetaminophen), ibuprofen, naloxone, naltrexone, and aspirin.
Tramadol, sold under the brand name Ultram among others, is an opioid pain medication and a serotonin–norepinephrine reuptake inhibitor (SNRI) used to treat moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an hour. It is also available by injection. It is available in combination with paracetamol (acetaminophen).
Opioids are a class of drugs that derive from, or mimic, natural substances found in the opium poppy plant. Opioids work in the brain to produce a variety of effects, including pain relief. As a class of substances, they act on opioid receptors to produce morphine-like effects.
Carisoprodol, sold under the brand name Soma among others, is a medication used for musculoskeletal pain. Use is only approved for up to three weeks. Effects generally begin within half an hour and last for up to six hours. It is taken orally.
Buprenorphine, sold under the brand name Subutex among others, is an opioid used to treat opioid use disorder, acute pain, and chronic pain. It can be used under the tongue (sublingual), in the cheek (buccal), by injection, as a skin patch (transdermal), or as an implant. For opioid use disorder, the patient must have moderate opioid withdrawal symptoms before buprenorphine can be administered under direct observation of a health-care provider.
Mitragyna speciosa is a tropical evergreen tree in the coffee family native to Southeast Asia. It is indigenous to Cambodia, Thailand, Indonesia, Malaysia, Myanmar, and Papua New Guinea, where it has been used in herbal medicine since at least the 19th century. It has also historically been used for chewing, smoking, and tea. Kratom has opiate properties and some stimulant-like effects.
Oxymorphone is a highly potent opioid analgesic indicated for treatment of severe pain. Pain relief after injection begins after about 5–10 minutes, after oral administration it begins after about 30 minutes, and lasts about 3–4 hours for immediate-release tablets and 12 hours for extended-release tablets. The elimination half-life of oxymorphone is much faster intravenously, and as such, the drug is most commonly used orally. Like oxycodone, which metabolizes to oxymorphone, oxymorphone has a high potential to be abused.
Dihydrocodeine is a semi-synthetic opioid analgesic prescribed for pain or severe dyspnea, or as an antitussive, either alone or compounded with paracetamol (acetaminophen) or aspirin. It was developed in Germany in 1908 and first marketed in 1911.
Dextropropoxyphene is an analgesic in the opioid category, patented in 1955 and manufactured by Eli Lilly and Company. It is an optical isomer of levopropoxyphene. It is intended to treat mild pain and also has antitussive and local anaesthetic effects. The drug has been taken off the market in Europe and the US due to concerns of fatal overdoses and heart arrhythmias. It is still available in Australia, albeit with restrictions after an application by its manufacturer to review its proposed banning. Its onset of analgesia is said to be 20–30 minutes and peak effects are seen about 1.5–2.0 hours after oral administration.
Meprobamate—marketed as Miltown by Wallace Laboratories and Equanil by Wyeth, among others—is a carbamate derivative used as an anxiolytic drug. It was the best-selling minor tranquilizer for a time, but has largely been replaced by the benzodiazepines due to their wider therapeutic index and lower incidence of serious side effects.
Nalbuphine, sold under the brand names Nubain among others, is an opioid analgesic which is used in the treatment of pain. It is given by injection into a vein, muscle, or fat.
Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, Papaver somniferum. It is typically used to treat mild to moderate degrees of pain. Greater benefit may occur when combined with paracetamol (acetaminophen) or a nonsteroidal anti-inflammatory drug (NSAID) such as aspirin or ibuprofen. Evidence does not support its use for acute cough suppression in children or adults. In Europe, it is not recommended as a cough medicine in those under 12 years of age. It is generally taken by mouth. It typically starts working after half an hour, with maximum effect at two hours. Its effects last for about four to six hours. Codeine exhibits abuse potential similar to other opioid medications, including a risk of habituation and overdose.
Tapentadol, brand names Nucynta among others, is a centrally acting opioid analgesic of the benzenoid class with a dual mode of action as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor (NRI). Analgesia occurs within 32 minutes of oral administration, and lasts for 4–6 hours.
Dezocine, sold under the brand name Dalgan, is an atypical opioid analgesic which is used in the treatment of pain. It is used by intravenous infusion and intramuscular injection.
An opioid overdose is toxicity due to excessive consumption of opioids, such as morphine, codeine, heroin, fentanyl, tramadol, and methadone. This preventable pathology can be fatal if it leads to respiratory depression, a lethal condition that can cause hypoxia from slow and shallow breathing. Other symptoms include small pupils, and unconsciousness; however, its onset can depend on the method of ingestion, the dosage and individual risk factors. Although there were over 110,000 deaths in 2017 due to opioids, individuals who survived also faced adverse complications, including permanent brain damage.
Isomethadone (INN, BAN; trade name Liden; also known as isoamidone) is a synthetic opioid analgesic and antitussive related to methadone that was used formerly as a pharmaceutical drug but is now no longer marketed. Isomethadone was used as both an analgesic and antitussive. It binds to and activates both the μ- and δ-opioid receptors, with the (S)-isomer being the more potent of the two enantiomers. Isomethadone is a Schedule II controlled substance in the United States, with an ACSCN of 9226 and a 2014 aggregate manufacturing quota of 5 g. The salts in use are the hydrobromide (HBr, free base conversion ratio 0.793), hydrochloride (HCl, 0.894), and HCl monohydrate (0.850). Isomethadone is also regulated internationally as a Schedule I controlled substance under the United Nations Single Convention on Narcotic Drugs of 1961.
Mitragynine is an indole-based alkaloid and the most abundant active alkaloid in the Southeast Asian plant Mitragyna speciosa, commonly known as kratom. The total alkaloid concentration in dried leaves ranges from 0.5 to 1.5%. In Thai varieties, mitragynine is the most abundant component while 7-hydroxymitragynine is a minor constituent. In Malaysian kratom varieties, mitragynine is present at lower concentration. Such preparations are orally consumed and typically involve dried kratom leaves which are brewed into tea or ground and placed into capsules. Mitragynine consumption for medicinal and recreation purposes dates back centuries, although early use was primarily limited to Southeast Asian countries such as Indonesia and Thailand where the plant grows indigenously. Recently, mitragynine use has spread throughout Europe and the Americas as both a recreational and medicinal drug. While research into the effects of kratom have begun to emerge, investigations on the active compound mitragynine are less common.
(what is this?) (verify) 
