The side effects of sympathomimetics range widely from nausea and dizziness to heart failure and death. Sympathomimetics are a class of drug that includes recreational drugs like cocaine and amphetamines, as well as ephedrine, which is found in some cold medicines. Certain drugs of this class may also be used as an appetite suppressant in obese patients, such as phentermine, benzphetamine, and phendimetrazine. These medicines are typically used on a short-term basis only, due to the risk of serious side effects.
Patients should discuss the possible side effects with their doctors before taking a drug. Side effects will vary widely, depending on which specific drug is prescribed. For example, phentermine may cause mild side effects like dry mouth, diarrhea, or constipation, as well as an unpleasant taste and vomiting. More serious side effects require urgent medical care, such as heart palpitations, chest pain, and shortness of breath. Other severe side effects of phentermine may include dizziness, insomnia, and increased blood pressure, as well as problems doing physical activities that were previously easy.
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Epinephrine, another sympathomimetic drug, can cause many of the same side effects as phentermine, such as dizziness. Its other mild side effects may include uncontrollable shaking of the hands, nervousness, and weakness. More serious side effects of epinephrine that require a doctor's care may include a rapid or irregular heartbeat, as well as difficulty breathing.
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Any drug, including sympathomimetics, may result in an allergic reaction. Patients who experience swelling of the face, lips, or throat should seek emergency medical care. Other signs of a possible allergic reaction to sympathomimetics can include hives, tightness in the throat, and problems breathing.
Recreational sympathomimetics, such as cocaine, can cause side effects like insomnia, cold sweats, and changes in blood pressure. Restlessness and anxiety are also common. Users may also experience nausea, vomiting, and loss of appetite, as well as damage to the nasal cavities and bleeding of the mucous membranes. Convulsions, heart attack, and stroke are also possible side effects of recreational sympathomimetics.
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In addition to these possible side effects, drug interactions can also occur. The medicines that may interact with sympathomimetics will vary, depending on the specific sympathomimetic drug that is prescribed. For example, antidepressants, digoxin, and monoamine oxidase inhibitor (MAOI) drugs may interact with epinephrine injections. Patients should always fully disclose their other medications and supplements before taking a new drug. They should also discuss any other medical conditions they have, such as high blood pressure, an overactive thyroid gland, or a history of heart attack with the prescribing doctor.