Sertraline should not be taken with or within two weeks of taking monoamine oxidase inhibitors (MAOIs). These include phenelzine (NardilÂ®), tranylcypromine (ParnateÂ®), isocarboxazid (MarplanÂ®), rasagiline (AzilectÂ®), and selegiline (EmsamÂ®).
Pure caffeine is a white, tasteless substance that makes up as much as 5% of. the weight of tea leaves. By structure, caffeine is closely related to the purine bases, guanine and adenine, found in deoxyribonucleic acids (DNA).
Caffeine molecule.EncyclopÃ¦dia Britannica, Inc. Pure caffeine (trimethylxanthine) occurs as a white powder or as silky needles, which melt at 238 Â°C (460 Â°F); it sublimes at 178 Â°C (352 Â°F) at atmospheric pressure. It is very soluble in hot water; upon cooling, the solution deposits crystals of caffeine monohydrate.