Analgesic Activity Of Ethanolic Extract Research Articles

Anti-Inflammatory and Analgesic Activity of Ethanolic Extract of Tubers and Different Fractions of Eulophia nuda Lindl.

Anti-Inflammatory and Analgesic Activity of Ethanolic Extract of Tubers and Different Fractions of Eulophia nuda Lindl.

In-vivo Pharmacological Evaluation of Analgesic Activity of Ethanolic Extract of Doronicum hookeri Clarke Rhizomes in Wistar Rats

A number of plants are used traditionally in different medical conditions by practitioners of traditional medicines but their claim is not yet evaluated scientifically in laboratory animals. Based on the ethnomedical claims made by the Unani health practitioners, the Clarke rhizomes of Doronicum Hookeri was evaluated for analgesics activity in rats to confirm its claim. The successive plant extraction was carried out using Soxhlet apparatus by employing ethanol as a solvent of the dried rhizomes of Doronicum Hookeri. The % yield of extracted compound was 28.27% w/w. The qualitative preliminary phytochemical screening revealed the presence of alkaloids, saponins, tannins, flavonoids, glycosides, phenolic content, terpenoids and volatile oils in the rhizomes of ethanolic extract of D. Hookeri. The extract was orally administered in rats at low dose and high dose (200 mg/kg, 400 mg/kg) and was evaluated using Eddy’s Hot Plate Method in rats for analgesics activity. Diclofenac sodium (50 mg/kg) and was taken as a standard drug. The maximum possible analgesia % of ethanolic extract of rhizomes of D. Hookeri were found to be highest at a dose of 400mg/kg which showed 68.95% and 80% analgesia at 45 minute and 60 minute which when compared to Diclofenac sodium showed 73.28% and 85.71% at 45 minute and 60 minutes. The analgesic efficacy of ethanolic extract of rhizomes of D. Hookeri showed significant analgesic activity (p<0.04) in dose dependent manner at different time intervals of 0, 15, 30, 45 and 60 min. This asserts ethnomedical claims of some tribes regarding the analgesic activity of this plant.
 Keywords - Analgesics, eddy’s hot plate, D. Hookeri, Diclofenac sodium.

Evaluation of the Analgesic Activity of Ethanolic Extract of Manilkara Zapota Seeds in Experimental Animal Model

Introduction: Non-Steroidal Anti-Inflammatory Drugs and opioids use remain the mainstay for pain treatment. However, both groups of drugs are well known for their common and severe side effects. Medicinal plants could be the better option to overcome these side effects. The anti-inflammatory activity of seeds of Manilkara zapota has already been demonstrated in experimental animals. As pain always accompanies inflammation, we have set forward a study to discover the analgesic activity of the ethanolic extract of Manilkara Zapota in animal models using Eddy's hot plate method. Aims and objectives: To explore the analgesic activity of ethanolic extract of Manilkara zapota seeds using Eddy's hot plate method. To compare the effect of ethanolic extract of Manilkara zapota seeds with the commonly used analgesic drug aspirin. Material and Methods: This study was conducted by using Eddy's hot plate method. A total of 12 Adult Wistar albino rats were grouped into three groups of 4 animals in each group. These groups were Group I: Control (normal saline), Group II: Standard (Aspirin 25mg per kg) Group III: Ethanolic extract of Manilkara zapota (200mg per kg). The reaction time was recorded at 0, 30, 60 & 90 minutes after injecting normal saline, standard drug, and extract. Result: The increase in mean reaction time of the extract was statistically significant (p< 0.0001) at 30, 60, and 90 min compared to that of the control. There was less increase in the reaction time of extract treated group compared to that of the aspirin-treated group at 30 min & 60 min points. Conclusion: The analgesic activity of the extract was significantly more than that of the control group. Peak analgesic activity occurred at 60 and 90 minutes.

Study on phytochemical, antioxidant and analgesic activity of ethanolic extract of Curcuma Amada Roxb Rhizome

Introduction: Curcuma amada Roxb. usually referred as ambahaldi is an exceptionally aromatic rhizomatic herb which contains number of phyto constituents responsible for several pharmacological activities. Present study is an attempt to explore antioxidant and analgesic activity of ethanolic extract of C. amada. Objectives: The goal of this work was to assess the antioxidant and analgesic activity of ethanolic extract of C. amada. Methods: For in-vitro antioxidant study, the DPPH (2, 2-Diphenyl-1-picrylhydrazyl) free radical scavenging test and nitric oxide scavenging assay was used to assess the antioxidant activity while the in-vivo analgesic efficacy was evaluated by using tail flick method and formalin induced pain in experimental animals. Different doses of 100mg/kg, 200 mg/kg, and 400 mg/kg was used to evaluate analgesic activity of ethanolic extract of C. amada. Results: Ethanolic extract of C. amada exhibited significant antioxidant in DPPH and nitric oxide scavenging assay. 100 mg/kg, 200 mg/kg, and 400 mg/kg of ethanolic extract of C. amada produced significant analgesic activity in tail flick and formalin induced pain model in experimental animals. Conclusion: Ethanolic extract of C. amada exhibited significant antioxidant as well as in-vivo analgesic activity in experimental animals.

Evaluation of the analgesic activity of ethanol extract of the stem and leaf of Cissus gracillis Gull and Perr (Vitaceae)

Cissus gracillis is used in the treatment of lumbago and pain. The analgesic activity of the ethanol extract of the stem and leaf of this plant was determined on mice and albino rats using radiant heat tail flick and acetic acid induced writhing assays. Extract was administered at doses of 125, 250 and 500 mg/kg through oral route. Phytochemical screening was done. Phytochemical screening showed presence of carbohydrates and terpenoids/steroids. In the tail flick assay, the difference in values was not statistically significant (P < 0.05, P < 0.001, P < 0.01) when compared with positive and negative control groups. There was a statistically significant (P<0.05) difference in the mean number of writhes between the extract treated groups and the negative control group. There was no statistically difference in the latency of the animals in the control and treatment groups in the tail flick assay. The findings of this study showed that ethanol extract of C. gracillis had significantly potent peripheral analgesic activity.

The Role of Andrographolide in Andrographis paniculata as a Potential Analgesic for Herbal Medicine based Drug Development

Background: Andrographis paniculata is a herbaceous plant in the Acanthaceae family, that is widely used as a traditional medicine in Asian countries and known to exhibit a wide range of pharmacological effects. Recent studies have provided an overview of the great potential of A. paniculata as an analgesic. The ethanol extract and ethyl acetate (EA) fraction of A.paniculata were shown to contain diterpene lactone compounds, which may be useful as a potential active ingredient in analgesic drugs. The development of a herbal medicine based drug requires an effective and high quality active ingredient. Therefore, this research was aimed to compare the analgesic activity of ethanol extract and EA fraction based on their andrographolide content and further to determine the more viable active substance for analgesic herbal medicine based drug development. Method: The andrographolide content in the ethanol extract and EA fraction was determined by High Pressure Liquid Chromatography (HPLC). Measurement of analgesic activity was performed by writhing test. The experimental animals were randomly divided into eight groups consisting of 5 mice in each. Group 1 (negative control) received 1% Tween-80 in normal saline. Group 2 (positive control) received a standard analgesic drug (diclofenac sodium) at a dose of 40 mg/kg body weight. Group 3, 4, and 5 received ethanol extract while Group 6, 7, and 8 received EA fraction, each at a dose of 12.5, 25, and 50 mg andrographolide/kg body weight, respectively. Each mouse was injected intraperitoneally with 1% acetic acid at a dose of 10 ml/kg body weight 30 minutes after oral administration of the treatments. The number of writhes were counted 5 min after acetic acid injection over a period of 45 min. Results: Andrographolide content in ethanol extract and EA fraction was 15.66±0.28 and 21.25±1.08 % w/w, respectively. Ethanol extract and EA fraction displayed analgesic activity of 67.68% and 70.91% respectively, at a dose of 50 mg andrographolide/kg body weight. The positive control at a dose of 40 mg/kg body weight showed an analgesic activity of 74.33%. Statistical analysis showed no significant differences between EA fraction at a dose of 50 mg andrographolide/kg body weight and ethanol extract at the same dose as well as the positive control (P> 0.05). The effective dose 50% (ED50) of the ethanol extract and EA fraction was determined to be 29.49 and 25.55 mg/kg body weight, respectively. Conclusion: It was possible to use andrographolide content as an indicator for the analgesic activity of A.paniculata. Ethanol extract and EA fraction of A. paniculata at the same dose of andrographolide showed similar analgesic activity. The amount of ethanol extract which needed to reach similar analgesic activity was higher than EA fraction. Therefore, EA fraction likely has greater potential as an analgesic active substance due to its higher content of andrographolide; however further study is needed to develop it as a dosage form.

Scientific Approaches in Screening the Analgesic property of Sida Cordata

Pain is likely the most common symptomatic complaint in medicine; an understanding of its mechanism is critical to interpret it. Nociception refers to the detection of noxious stimuli by nociceptors, followed by transduction and transmission of the sensory nervous information from the periphery to the brain. Plants have played a unique holistic role for the provision of food, drugs, clothing, shelter, etc. Natural compounds have been extensively explored for new drug discoveries. Indeed, plants have been used as medicines for more than 5000 years, as a source of antibiotics, antineoplastic, analgesics, cardioprotective, among others. About 70–90% of the population in developing countries continue to use ancient medicines based on plant extracts. Sida cordata popularly known as “bala” is regarded as a valuable drug in the Ayurvedic System of Indian Medicine. In order to validate the ethnomedical claim of Sida cordata as pain reliever, a study was conducted to evaluate the analgesic activity of ethanolic extract of Sida cordata whole plant in laboratory animals. For centrally mediated analgesic activity, eddy’s hot plate method was employed and Pentazocine was uses as reference control. For peripherally mediated analgesic activity, acetic acid induced writhing model was employed and Dicofenac was used as reference control. Sida cordata ethanolic extract was administered orally at the doses of 100 and 200 mg/kg. In eddy’s hot plate method, both the doses of Sida cordata significantly increased the reaction time compare to vehicle control. In acetic acid induced writhing test, both the doses of Sida cordata significantly reduced the number of writhing compare to vehicle control. In both the models, the effect produced by Sida cordata was comparable to that of respective reference control. The results obtained suggest that the ethanolic extract of Sida cordata has showed marked analgesic activity in experimental animal models and this strappingly supports the ethnopharmacological applications of the plant for the target activity.

Evaluation of analgesic activity of ethanolic extract of alpinia galanga rhizomes in experimental animal models

Introduction: Alpinia galanga Linn is a widely used medicinal plant. It is also known as Greater Galangal and belongs to family Zingiberaceae. The plant is a perennial rhizomatous herb and has been claimed to possess analgesic activity apart from many medicinal properties. Objectives: The aim of the present study was to evaluate the analgesic activity of ethanolic extract of alpinia galanga rhizomes (EEAGR) in experimental animals. Methods: Acute toxicity test was done following the Organization of Economic Cooperation and Development guidelines.100 mg/kg, 200 mg/kg, and 400 mg/kg body weight [b.w] of ethanolic extract of alpinia galanga rhizomes was given orally to experimental animals. EEAGR was evaluated for central analgesic activity by using the tail flick method and peripheral analgesic activity by using the acetic acid induced writhing test using aspirin (300 mg/kg b.w and 100 mg/kg b.w orally) as the standard drug respectively. Results: EEAGR at 400mg/kg produced highly significant and greater analgesic activity than Aspirin (standard drug) in tail flick method. EEAGR at dose 400mg/kg has shown comparable reduction in mean total number of writhings which is equivalent to that of Aspirin (standard drug) in writhing test. Conclusion: EEAGR has significant central and peripheral analgesic activity. Keywords: Alpinia galanga, Analgesic, Pain, Tail flick, Writhing.

Evaluation of the analgesic activity of ethanolic extract of Populus deltoides leaves in mice

The ethanolic leaves extract of Populus deltoides was tested for the presence of various phytoconstituents and designed to evaluate the analgesic activity in mice. The peripheral analgesic activity of ethanolic leaves extract of P.deltoides (250 and 500 mg/kg) was studied by using acetic acid stimulated writhing test and central analgesic activity of P.deltoides was studied by using hotplate process. The ethanolic leaves extract of P.deltoides professed the existence of a variety of chemical constituents like alkaloids, saponins, flavonoids, terpenes and steroids. Leaves extract of P.deltoides appreciably decreased the writhing actions in acetic acid-induced writhing test in mice and amplified the respond time in hotplate test. These results suggest that the extract may have NSAIDs like activity through the peripheral mechanism and central analgesic activities via opioid receptors. From our study, we endowed that leaves extract of P.deltoides has feasible to analgesic activity. This study reveals that it can be used in the management of pain and provide a scientific basis for its traditional use.

A Original Article ANALGESIC ACTIVITY OF BARK AND LEAVES OF FICUS RELIGIOSA L. FROM NEPAL

Objective: Because of adverse side effects, caused by NSAIDs, tolerance, and dependence induced by opiates, the use of these analgesic agents has not been successful in all cases. Therefore, alternative analgesic drugs from plant sources are the new target now days. The objective of this study was to evaluate the analgesic activity of ethanolic extracts of stem barks and leaves of Ficus religiosa.
 Methods: The analgesic activity of ethanolic extract of stem barks and leaves was evaluated in the Swiss albino mice model using acetic acid-induced writing response and Eddy’s hot plate method. Analgesic activity was demonstrated with the percentage inhibition of acetic acid induced writings and the percentage increased in latency time of paw licking. The potency of test extracts was compared with standard drug, Diclofenac.
 Results: Ethanolic extract of leaves and bark of F. religiosa showed potential analgesic activity from both methods. From Eddy’s hot plate model, it was observed that the percentage of increased latency time at 90 min by ethanolic extract of leaves and stem bark was found to be 70.81 % (8.54 min) and 70.78 % (8.53 min) respectively at a dose of 400 mg/kg. Both of these results are statistically significant (p<0.05) as compared to the test group. Furthermore, both of these extracts showed the dose-dependent and time-dependent increased in latency time and these results are compared to that of standard drug Diclofenac. Similarly, ethanolic extract of leaves and stem at 400 mg/kg significantly inhibited the number of writhings induced by acetic acid. The percentage inhibition of writhings by ethanolic extract of leaves at a dose of 400 mg/kg was 68.47 % which was similar to that of standard drug Diclofenac (68.47 %). However, ethanolic extract of bark showed relatively lower percentage inhibition (60.79 %) as compared to leaf extract and standard, but the result was significant as compared to that of the test group (p<0.05).
 Conclusion: Ethanolic extracts of F. religiosa stem bark and leaf possess both central and peripheral analgesic properties and these effects may be beneficial for the management of pain.

KULIT BUAH JERUK LIMAU (Citrus amblycarpa (Hassk.) Osche) SEBAGAI ANALGESIK

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the treatment options for relieving pain. However, long-term use can trigger gastrointestinal bleeding. Therefore, alternative analgesics which have the same therapeutic effect with lower side effects are needed. Limau (Citrus amblycarpa) is an empirical drug for tingling and cramping. The aim of the study is to determine the analgesic activity of ethanol extract of C. amblycarpa fruit peel. The method used in testing analgesic activity is the Hot Plate method. The study was conducted by dividing 30 mice into 6 groups. The group given CMC-Na 1% was used as a negative control, the group given suspension of sodium diclofenac dose of 6.5 mg/kg of body weight was used as a positive control, and the group given suspension of ethanol extract of C. amblycarpa fruit peel with dose variations 100, 300 and 600 mg/kg of body weight. The test animals were placed on top of the Hot Plate with a temperature of 70°C at 30 minutes after giving suspension test and the response time of mice to heat was observed every 30 minutes for 3 hours with cut off time 15 second. Based on the test results, it can be concluded that the administration of ethanol extract of C. amblycarpa fruit peel with 100, 300 and 600 mg/kg of body weight gave analgesic activity on mice compared to the negative controls (CMC-Na 1%).
 
 Keywords: C. amblycarpa, Fruit Peel, Analgesics, Hot Plate

Evaluation of dose dependent analgesic response by extracts of Myristica fragrans on albino wistar rats: an experimental study

Background: The objective of the study was to evaluate analgesic activity of ethanolic extract, methanol and benzene fraction of Myristica fragrans on wistar albino rats.Methods: The present study was carried out in the department of pharmacology JNMC AMU and F.H. Medical College, Agra. The analgesic activity was evaluated by employing the Eddy’s hot plate method and tail flick response method. In both the tests, Rats of either sex weighing 150-200 g were used. The total number of animals n=36 were allocated to six groups. Each group consist of six animals each. The response noted in animals that were tested by hot plate method was reaction time for licking/biting of both the paws before and after administration of control & test drugs. However in Tail flick test, the pain threshold response was recorded before and after administration of control & test drugs. The statistical analysis was done by using one-way ANOVA. The data is expressed as Mean±SEM. P<0.05 was considered to be statistically significant.Results: Ethanolic extracts and methanol fraction of M. fragrans showed statistically significant (p<0.001) increase in reaction time for licking/biting in hot plate method. On the contrary a significant increase in pain threshold was also recorded in tail flick response test. It is interesting to note that no significant degree of analgesia related to any dose of benzene fraction was observed.Conclusions: The present study reveals the dose dependent significant analgesic activity of the extracts of M. fragrans i.e. ethanolic extracts and methanol fraction in both the test. However, the degree of analgesia was recorded significantly higher in groups received higher doses of extracts of M. fragrans.

Analgesic and anti-inflammatory activities of ethanol extract of Hymenodictyon pachyantha K.Krause stem bark

The cost and worrisome toxicities associated with currently available anti-inflammatory drugs necessitate continuous search for more effective, cheap, and safe anti-inflammatory agents. This study investigated the anti-inflammatory and analgesic activities of ethanol extract of Hymenodictyon pachyantha stem bark (EEHP). The anti-inflammatory activity of EEHP was evaluated by determining its effect on egg albumin–induced rat paw edema, phospholipase A2 (PLA2) activity, calcium chloride (CaCl2)–induced platelet aggregatory response, and membrane stabilization. The effect of EEHP on acetic acid–induced writhing responses was used as a model for analgesic property. The presence of flavonoids, terpenoids, steroids, saponins, alkaloids, tannins, and phenols was detected in EEHP. There was no sign of toxicity and mortality 24 h post-EEHP administration, suggesting that it is safe up to 5000 mg/kg b.w. EEHP significantly inhibited egg albumin–induced rat paw edema, in a dose-dependent manner and in both early and late stages of inflammation. Similarly, EEHP significantly inhibited PLA2 activity and platelet aggregatory response. EEHP also inhibited hypotonic-induced haemolysis by 23.99, 54.99, and 92.68% at 0.2, 0.6, and 1.0 mg/ml respectively. Similarly, EEHP produced 44.64, 58.04, and 70.54% reduction in the number of writhings induced by acetic acid at 200, 400, and 600 mg/kg p.o. respectively. These results demonstrated that EEHP has analgesic and anti-inflammatory effects. The results also showed that the mechanisms of the anti-inflammatory effect may be by inhibiting PLA2 and aggregation of platelets, and stabilization of lysosomal membrane.

Central analgesic activity of ethanolic extract of Moringa oleifera seeds

Background: Moringa oleifera Lam. commonly known as the drumstick tree is an exceptionally nutritious vegetable tree with a variety of potential medicinal uses. Aims and Objectives: The objective of this study was to evaluate the central analgesic activity of ethanolic extract of M. oleifera (EEMO) seeds. Materials and Methods: The central analgesic activity was studied using Eddy’s hot plate method and tail immersion method in Albino Wistar rats of either sex weighing 150–200 g at doses of EEMO 50 mg/kg, 100 mg/kg, and 200 mg/kg. Statistical significance was calculated using one-way analysis of variance followed by post hoc Dunnett’s test. Results: EEMO at all three doses 50 mg/kg, 100 mg/kg, and 200 mg/kg exhibited central analgesic activity by significantly increasing the reaction time in Eddy’s hot plate method and tail immersion method when compared to control group. Conclusion: EEMO seeds exhibit central analgesic activity in experimental animals.

Peripheral and central analgesic activity evaluation of ethanolic extract of Vitex Negundo flowers in experimental animals

Background: Vitex negundo Linn (Family: Verbenaceae), locally known as ‘Nirgundi’ an important medicinal plant is a woody, aromatic shrub growing to a small tree. It commonly bears tri- or penta-foliate leaves on quadrangular branches, which give rise to bluish-purple coloured flowers in branched tomentose cymes. It has been claimed to possess analgesic activity apart from many medicinal properties. The aim of the present study was to evaluate both the peripheral and central analgesic activity of ethanolic extract of Vitex negundo flowers (EEVNF) in experimental animals.Methods: Acute toxicity test was done following the Organization of Economic Cooperation and Development guidelines. EEVNF (100mg/kg, 200mg/kg, and 400 mg/kg body weight [b.w.] p.o) was evaluated for peripheral analgesic activity by the acetic acid (0.7%) induced writhing test and central analgesic activity by the tail flick method respectively using aspirin (100mg/kg b.w. and 300mg/kg b.w.) as the standard drug.Results: EEVNF significantly decreased the number of writhing in writhing test at all the doses (p<0.001) and increased the reaction time in tail-flick method (p<0.001) at all the doses when compared to control. EEVNF in the dosage of 400mg/kg b.w. produced analgesic effects which was comparable with that of the standard drug aspirin at dose 100mg/kg b.w in writhing test and produced greater analgesic activity than that of standard drug aspirin at dose 300mg/kg b.w in tail flick method.Conclusions: EEVNF has significant peripheral and central analgesic activity.

Analgesic and anti-Inflammatory activity of Tradescantia fluminensis leaves extract

Objective: The present study sought to evaluate the anti-inflammatory and analgesic activities of ethanolic extract from Tradescantia fluminensis leaves. Methods: The crude leaf extract of T. fluminensis was investigated for anti-inflammatory and analgesic activities in Wistar Albino rats and mice respectively. The anti-inflammatory activity was investigated using egg albumin induced oedema model while acetic acid and formalin-induced paw licking models were used to evaluate the analgesic activity. Results: The extract showed a significant (P<0.05) dose-dependent inhibition of inflammation and pain compared to the control group. Conclusion: The leaf extract possesses anti-inflammatory and analgesic activities. The activities could be attributed to phytochemicals present in the plant.

Analgesic activity of ethanolic extract of flower of Lantana camara

The flower of the plant Lantana camara were extracted with ethanolic solvents and screened for their analgesic activity. The ethanolic extract of the plant Lantana camara has showed the presence of flavonoids. The analgesic activity of different extracts of Lantana camara flower is evaluated by tail flik methods where the responses are jumping withdrawal of paws and licking of paws. This study demonstrates that flower powder of Lantana camara has significant analgesic activities.

Anti-inflammatory and analgesic activity of Punarnavashtak Kwath, an ayurvedic formulation

Context: Punarnavashtak Kwath (PNK) is a polyherbal formulation assumed to have the potential for curing all types of inflammation, hepatic disorders, and asthma. Aims: This study was conducted to establish the anti-inflammatory and analgesic activity of ethanol extract of PNK (EEPNK) in albino rats and mice. Subjects and Methods: The parts of the plant were air -dried in shade and pulverized coarsely and sieved by 20# sieve. Powdered material of plant was defatted with pet ether for 1 day followed by Soxhlet extraction with ethanol (95% v/v) for 7 days. The anti-inflammatory activity of the EEPNK was evaluated by egg albumin-induced paw edema and cotton pellet-induced granuloma tests to establish its effect on acute and chronic stage of inflammation models in albino rats. Whereas analgesic effects of EEPNK were performed in mice of either sex by acetic acid-induced writhing and hot plate methods. Statistics was expressed as a mean ± standard error of mean and statistical analysis was carried out by one-way ANOVA with Tukey's test. Results: The percent inhibition in rat paw volume was dose dependent (79.14%, 68.51%, and 61.70% at doses of 400, 200, and 100 mg/kg, p.o., respectively) at 240 min readings. Cotton pellet granuloma in rats (chronic study) model EEPNK (400, 200 and 100 mg/kg, p.o.) extensively decreased the granuloma weight as compared to the negative control animals. Pretreatment with EEPNK was (400, 200, and 100 mg/kg p.o.) extensively ( P P Conclusions: Distinguish with the standard drug (indomethacin), the elevated dose of EEPNK (400 mg/kg b.w.) has a comparable effect on the anti-inflammatory and analgesic activities.

Phytochemical Screening and Evaluation of Analgesic Activity of Oroxylum indicum.

We aimed to study phytochemical screening and analgesic activity of ethanol extract of Oroxylum indicum. The dried powder of the barks of the plant was extracted with 95% ethanol and was subjected to various phytochemical tests to ascertain the principle constituents contained in the extract. The result revealed the presence of alkaloids, flavonoids, tannins, glycosides in the ethanol extract of Oroxylum indicum. The extract was screened for analgesic activity by using hot plate, acetic acid-induced writhing and formalin test. The ethanol extract of the plant at two different doses (250 and 500 mg/kg) showed significant (P<0.05) analgesic effect in all test methods (hot plate, acetic acid-induced writhing and formalin). The analgesic activity was compared with a standard drug (ketorolac at 10 mg/kg). Based on the present findings and previous literature review it can be concluded that flavonoids and tannins might be responsible for the analgesic activity. We suggest that ethanol extract of Oroxylum indicum might have potential chemical constituents that could be used in the future for the development of novel analgesic agent.

Analgesic activity of ethanolic extract of leaves of Nyctanthes arbor-tristis linn on experimental animal models

Background: The present study has been undertaken to evaluate the pharmacological efficacy of ethanolic extract of leaves of Nyctanthes arbor-tristis (EENA) LINN as an analgesic agent in comparison with standard non-steroidal anti-inflammatory agents. Methods: The extract was prepared by soxhlet method and acute toxicity test was performed as per OECD guidelines. The peripheral analgesic activity was assessed using acetic acid induced writhing method. The central analgesic activity was assessed using tail-flick method. Results: It has been shown that EENA 400mg/kg and aspirin 100mg/kg significantly increased the pain threshold as assessed by increase in the latency period or basal reaction time. EENA (200mg, 400 mg/kg) and aspirin 100 mg/kg also significantly reduced acetic acid induced writhing response showing peripheral analgesic activity. Conclusions: Since prostaglandins are involved in the pain perception and are inhibited by flavonoids, it could be suggested that the analgesic effect of Nyctanthes arbortristis might be due to its inhibitory action on PG biosynthesis.