Inadequate level of extracellular serotonin can cause anxiety disorders or anxious responses, such as fear of height. Selective Serotonin reuptake inhibitor (SSRIs), a class of drugs, which are antidepressant, and benzodiazepines, can be used in treating such that condition by increasing the level of extracellular serotonin. Celexa is an antidepressant used to treat depression as well as various forms of anxiety. One of the previous studies investigated the contribution of individual serotonin (5-hydroxytryptamine; 5-HT) receptors to mood control by using homologous recombination to generate mice lacking specific serotonergic receptor subtypes; They have demonstrated that mice without 5-HT1A receptors display decreased exploratory activity and increased fear of aversive environments (open or elevated spaces). They have also demonstrated that that. 5-HT1A knockout mice also exhibited a decreased immobility in the forced swim test, an effect commonly associated with antidepressant treatment. Despite of number of promising studies into using virtual reality as a treatment for anxiety (fear of height), still there is a concern for not fully being responsiveness in some patients, or drug infarctions of SSRIs with other meds patients are taking, or the side effects of it that makes us seeking for a possible substituted treatment with hopefully a similar or even better effects, regarding to less side effect, which usually may be found in natural or homeopathic drugs and remedies. Numerous studies have been performed to study the effectiveness of homeopathic therapy for anxiety and depression, however there should be more research done in homeopathic field. Funding has been limited, because homeopathic medicines cannot be patented. There are no profits to be made from investments in research. Even though it has been proven that homeopathic remedies are more effective than placebo, small sample size has been another issue as it makes it more difficult to demonstrate statistically significant results. There are barriers in this field that makes research limited, however the natural therapy that tends to treat individuals based on their symptoms have the least or non side effects, and that is why this field needs more researches. For example, Calcarea Carbanica is a homeopathic remedy that can be used in treating fear of height, and if the benefits of using this remedy will be shown over the common SSRIs that is used to treat the problem, then that may lead to more clinical research trials to compare the effect of such homeopathic remedies versus the current pharmacological agents that may cause side effects or possible drug interactions or dependence and withdrawal issues. Homeopathic Remedies are made based on the homeopathic pharmacopeia guidelines. Homeopathic potency dosing units have been defined as “C”. For the deeper level of the symptoms, when lots of emotional and physiological symptoms are seen, they may choose a higher potency. Calcarea carbonica, a homeopathic remedy is composed of calcium carbonate. Calcium carbonate itself is not effective to treat anxiety though, but the homeopathic remedy, Calcarea carbonica, as a whole has been used to overcome the anxiety problem, such as fear of height.