Hello, With reference to your query that you are already suffering from anxiety disorders and on top of it you smoked marijuana last night and feeling uneasy since then. However let me give some facts about marijuana and its effects on the individual. Marijuana is a combination of shredded leaves, stems and flower buds of the cannabis saliva plant. It is a commonly used illegal drug. It is usually smoked but can also be eaten mixed with food or brewed as tea. Smoking triggers effects faster than taking orally. The psychological effects will start to appear within 30-60 minutes as tetrahydrocannabinol (THC) is absorbed with the blood through lungs and circulated around the body. If you ingest it will take 2 to 3 hours to show the effects. It can relieve pain, control nausea and increase in appetite. It can also cause acute psychosis. It can cause short-term memory and learning problems, dry mouth, impaired motor skills and red eyes. It also increases the heart rate. In some cases it increases double and if you are already suffering from heart disease, there will be a risk too. Some feel relaxed after using marijuana and some develop anxiety and paranoia. Person's reaction to the drug depends on the individual, strength of the marijuana used and the person who smoked the drug. Tetra hydrocannabinol (THC) binds to nerve cells in the body, where the cannabinoid receptors are present and changes the activity of that nerve cell. It is known to decrease pressure in the eyes, raise anxiety and cause paranoia. In addition you are already taking Citalopram, which is a selective Serotonin reuptake inhibitor, and like to cause drug interactions. Hence it is advisable for you to contact your GP to rule out any possible side effects on your heart. Thank you.