The prevalence of back pain among pregnant women is high, with varying characteristics. The degree of disability is usually moderate and the presence of urinary infection and higher disability scores were associated with greater intensity of low back pain.

Pain is recognized as one of the main symptoms in knee osteoarthritis and is the main reason why patients seek medical attention. Scoparia dulcis has been popularly used to relieve discomfort caused by various painful conditions. The objective of the study is to evaluate the analgesic and anti-inflammatory effect of the crude extract of S. dulcis, in an experimental model of osteoarthritis. The experiment was performed with Wistar rats divided into 4 groups with 5 animals each: healthy, saline, crude extract, and meloxicam groups. Knee osteoarthritis was induced by intra-articular injection of sodium mono-iodoacetate. First, clinical parameters of pain were assessed at days 0, 5, 10, 15, and 20 after induction. Second, the potential cyclooxygenase inhibition was evaluated, and the cytokines of the synovial fluid were quantified. An in silico test and Molecular Docking tests were performed. A histopathological evaluation was made on articular cartilage with safranin O staining. The results showed that a 15-day treatment with crude extract reduced edema, spontaneous pain, peripheral nociceptive activity, and proinflammatory cytokines in the synovial fluid. The highest inhibition of cyclooxygenase 2 in the crude extract occurred at 50 µg/mL. The crude extract of S. dulcis presents therapeutic potential for the treatment of osteoarthritis due to its anti-inflammatory and anti-nociceptive action.

The use of medicinal plants is a part of human evolution and plays an important role in the treatment of numerous diseases. Neuropathic pain is caused by an injury or disease of the somatosensory nervous system, which affects about 8% of the world population, and its management is considered a great challenge. In the search for new therapies, Arrabidaea chica (Humb. & Bonpl) Verlot, (A. chica), popularly known as carajirú and pariri, whose anti-inflammatory properties are scientifically proven and without evidence of neuropathic pain, appears in this scenario. The objective of this study was to evaluate the efficacy of fractions of the ethanolic extract of Arrabidaea chica in an experimental model of neuropathic pain induced by compression of the main trunk of the ciatic nerve in Wistar rats. After obtaining the extract by maceration with ethanol, fractionation was carried out to obtain fractions: hexane, chloroform, ethyl acetate and butanol. In vivo studies were performed using the von Frey, Rotarod and Weight bearing tests. The animals were treated for 15 days with the fractions of Arrabidaea chica at the dose 1 mg/kg/day. Gabapentin (1 mg/kg v.o) was used as a positive control. The pharmacological study significantly attenuated the behavioral manifestations of neuropathic pain in the animals treated with the fractions of the ethanolic extract of Arrabidaea the dose 1 mg/Kg v.o, compared to the saline group (0.1 ml/kg), confirming the antinociceptive action and antioxidants of the plant. In conclusion, the results of this study suggest that the fractions of Arrabidaea chica present therapeutic potential for the treatment of neuropathic pain and/or adjuvant in the conventional treatment of the same.