Cardiovascular effects

Abnormal heartbeat (also called an arrhythmia or dysrhythmia) is defined as a problem with the rate or rhythm of a heartbeat.^[1] A heartbeat that is too fast (greater than 100 beats per minute) is called tachycardia and a heartbeat that is too slow (less than 60 beats per minute) is called bradycardia. Arrhythmias are caused by changes to heart tissue. Hearts beat due to cascading electrical signals and these can be influenced by stress hormones, electrolytes, and medicinal substances.

An abnormal heartbeat is most commonly induced under the influence of moderate dosages of stimulant and depressant compounds, such as cocaine,^{[2][3][4][5][6][7][8]} amphetamines,^{[9][10][11][12][13]} alcohol,^[13] and opioids.^[13][14][15] While stimulants tend to increase a person's heart rate, depressants tend to decrease it. Combining the two can often result in dangerously irregular heartbeats.

Decreased blood pressure can be described as a condition in which the pressure in the systemic arteries is decreased to abnormal levels. A blood pressure of 120/80 is considered normal for an adult. A blood pressure of 90/60 or lower is considered hypotension and a blood pressure between 120/80 and 90/60 is considered prehypotension.^[16]

Decreased blood pressure is most commonly induced under the influence of moderate dosages of GABAergic depressant compounds, such as benzodiazepines and barbiturates. However, it can also occur under the influence of vasodilating compounds such as poppers as well as certain psychedelics and stimulants in an unpredictable manner.

Decreased heart rate or bradycardia can be described as a heart rate that is lower than the normal heart rate at rest. The average healthy human heart normally beats 60 to 100 times a minute when a person is at rest. When the heart rate fluctuates to lower levels under 60 BPM, it is described as bradycardia or an abnormally low heart rate.

It is worth noting that decreased heart rate can often be a result of psychological symptoms as a natural response to relaxation, anxiety suppression, sedation, and mindfulness.

Decreased heart rate is most commonly induced under the influence of heavy dosages of depressant compounds, such as GABAergics, and opioids. However, it can also occur under the influence of cannabinoids, dissociatives, and stimulants.

Increased blood pressure can be described as a condition in which the pressure in the systemic arteries is elevated to abnormal levels. A blood pressure of 120/80 is considered normal for an adult. A blood pressure of 90/60 or lower is considered hypotension and a blood pressure between 120/80 and 90/60 is considered prehypotension.^[17] Conversely a blood pressure greater than 120/80 and less than 139/89 is considered prehypertension.

Within the medical literature, a situation in which a person's blood pressure is very high (e.g., >180/>110 mmHg) with minimal or no symptoms, and no signs or symptoms indicating acute organ damage is referred to as a "hypertensive urgency".^[18] In contrast, a situation where severe blood pressure is accompanied by evidence of progressive organ or system damage is referred to as a "hypertensive emergency".

Increased blood pressure is most commonly induced under the influence of heavy dosages of vasoconstricting compounds, such as traditional stimulants and stimulating psychedelics.

Increased heart rate or tachycardia is described as a heart rate that is faster than the normal heart rate at rest. The average healthy human heart normally beats 60 to 100 times a minute when a person is at rest. When the heart rate fluctuates to higher levels over 100 BPM, it is described as tachycardia or an abnormally high heart rate.

It is worth noting that increased heart rate can often be a result of psychological symptoms as a natural adrenal response to anxiety, paranoia, shock, and fear.

Increased heart rate is most commonly induced under the influence of heavy dosages of stimulating compounds, such as traditional stimulants, certain psychedelics, and certain dissociatives. This is thought to occur as a direct result of dopaminergic or adrenergic modulation.^[19][20] However, it can also occur under the influence of deliriants due to the way in which they inhibit acetylcholine, one of the main modulaters of heart rate in the peripheral nervous system.^[21][22]

Vasoconstriction can be described as a narrowing of the veins and blood vessels which results from a contraction of their muscular wall. It is particularly prevalent in the large arteries and small arterioles.

This effect typically results in feelings of tightness, achiness, and numbness within a person's arms and legs. It can range from mild in its effects to extremely uncomfortable.

Vasoconstriction is often accompanied by other coinciding effects such as stimulation. It is most commonly induced under the influence of moderate dosages of stimulating psychedelic compounds, such as LSD, 2C-E, and DOC. However, it can also occur under the influence of traditional stimulants such as methamphetamine, caffeine, and MDMA.

Vasodilation can be described as a widening of the veins and blood vessels which results from the relaxation of smooth muscle cells within the vessel walls. It is particularly prevalent in the large arteries and small arterioles. The primary function of vasodilation is to increase blood flow in the body to tissues that need it most. In essence, this process is the opposite of vasoconstriction, which is the narrowing of blood vessels.

This effect is typically very difficult to consciously perceive but often results in a bloodshot red eye effect and relief from glaucoma.

Vasodilation is often accompanied by other coinciding effects such as decreased blood pressure. It is most commonly induced under the influence of moderate dosages of cannabinoid compounds, such as cannabis, JWH-018, and THJ-018. However, it can also occur under the influence of poppers and viagra.

• Subjective effect index
• Physical effects