Bucetin [(3-hydroxy-p-butyrophenetidide) CAS: 1083-57-4) is a homologue to phenacetin and is used instead of phenacetin as an analgesic drug because of its lower toxicity than that of phenacetin, despite having equivalent analgesic activity when used at an appropriate dose. Dysplastic lesions of the proximal tubules were frequently seen in the males given bucetin in a dose-related fashion.

Imidazole salicylate (also known as ITF-182), a nonsteroidal anti-inflammatory drug (NSAID) that inhibits Tromboxane A2 synthesis, without interfering with cyclo-oxygenase pathway and possesses the limited inhibitory effects on prostaglandin synthesis. Imidazole salicylate can be used for the treatment of osteoarthrosis and musculoskeletal trauma. In addition, it can be given to patients with decompensated cirrhosis without risk of inhibiting kidney prostaglandin synthesis. Imidazole salicylate was characterized by good gastric tolerability and could be assigned for treatment of rheumatic diseases in the elderly. The drug also can be safely used in aspirin-sensitive patients.

Flumedroxone is a progestative agent. It is a pregnane derivative substituted at C-6 by a trifluoromethyl group. It was tested whether flumedroxone had prophylactic value in migraine. No benefit was found in males, or in females with no history of menstrual exacerbation of migraine. In women whose migraine was worse around the time of menstruation flumedroxone resulted in statistically fewer headaches of less severity. With the dose used in this trial side-effects were frequent, the commonest being polymenorrhagia, which occurred in half the women of reproductive age.

Propacetamol is a bioprecursor of paracetamol. It is rapidly hydrolyzed by plasma esterases and releases its constituent paracetamol by the end of its intravenous or intramuscular administration. Its metabolism is identical to that of paracetamol. It is used in post-operative care and is delivered by I.V. It is given if the patient is unable to take oral or rectally delivered paracetamol and non-steroidal anti-inflammatory drugs are contraindicated. The onset of analgaesia from propacetamol is more rapid than paracetamol given orally. 2 g of propacetamol are equivalent to 1g of paracetamol.

1,6-Dimethyl-3-carbethoxy-4-oxo-6,7,8,9-tetrahydro-homopyrimidazol (rimazolium, MZ-144) is an analgesic (non-narcotic). It proved to be effective in all the analgesic assays used (independently of the nociceptive stimulus applied) (hot plate, tail flick, writhing tests, Randall-Selitto test, tail clip, surgical pain) differing in this respect from the nonsteroidal antiinflammatory analgetics. Rimazolium lacks the capacity of producing opiate-like physiological dependence. Also rimazolium fails to show any indication of narcotic-like abuse liability by any of clinical assessments. Rimazolium is registered in Hungary under the brand name Probon. In Hungary among analgesics Probon is the first of choice especially in case of chronic pain accompanying chronic respiratory tract diseases.

Dextromoramide is a synthetic strong-acting opioid and full mu-opioid receptor agonist. Dextromoramide is a Schedule I drug illegal to possess. The current indication for Palfium® (dextromoramide) is severe acute or chronic pain requiring opioids, such as post-operative pain, and pain associated with bone fractures, malignancies and acute renal/biliary colic attacks in adults.

Flupirtine is a triaminopyridine derivative having a chemical structure - 2-amino-3-ethoxy-carbonylamino-6-4-fluoro-benzylamino-pyridine. The basic molecule used for synthesis of flupirtine was 2, 6-dichoro 3-nitropyridine. It was first synthesized in 1980s in Germany and was marketed by Degussa Pharma. Flupirtine is a centrally acting, non-opioid analgesic that is available in a number of European countries for the treatment of a variety of pain states. The therapeutic benefits seen with flupirtine relate to its unique pharmacological properties. Flupirtine displays indirect NDMA receptor antagonism via activation of potassium channels and is the first representative of a pharmacological class denoted the 'selective neuronal potassium channel openers'. The generation of the M-current is facilitated by flupirtine via the opening of neuronal Kv7 potassium channels. The opening of these channels inhibits exaggerated neuronal action potential generation and controls neuronal excitability. Neuronal hyperexcitability is a physiological component of many pain states such as chronic pain, migraine and neurogenic pain.

Ketobemidone (Cliradon, Ketogan, Ketodur, Cymidon) is a strong opioid analgesic, structurally related to pethidine, which has been in clinical use for more than 50 years. In the Scandinavian countries ketobemidone is only available in combination with a spasmolytic substance N,N-dimethyl-3,3-diphenyl-I-methylallylamine (A29). Ketobemidone has been shown to be a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist. In spite of a relatively low mu-receptor affinity ketobemidone has a higher analgesic potency than morphine by systemic administration. It is probably due to its higher lipophilicity and consequently more easy penetration into the CNS. Ketobemidone is indicated for the treatment of all types of severe pain, such as postoperative, cancer, kidney stones and fractures.

Nifenazone is a drug that has been used as an analgesic for a number of rheumatic conditions. Later it was shown that nifenazone is not of significant value in the therapy of the chronic rheumatic disorders and that side-effects may be expected to occur, particularly in those patients who give a history of abnormal reactions to phenylbutazone and oxyphenbutazone.

Dipyrocetyl (2,3-diacetyloxybenzoic acid) is a drug used as an analgesics and antipyretics. Besides, was shown, that it may be useful in the treatment of acute lung injury (ALI) associated with acute respiratory distress syndrome (ARDS). Dipyrocetyl possesses the anticoagulation properties, which may contribute directly to improve tissue integrity as well as indirectly by the prevention of activation of pro-inflammatory cytokines. In addition, was made a suggestion, that the drug may function as an MMP inhibitor.