Caffeine Beta blockers

Thyroid supplement Blood pressure medications Beta blockers Thiazide diuretics Alpha methyl DOPA Appetite suppressants Phentermine Sibutramine Other Alcohol Caffeine Cocaine Nicotine... 

Smoking cessation, with or without nicotine substitutes, may alter response to concomitant medication in ex-smokers. Smoking may affect alcohol, benzodiazepines, beta-adrenergic blockers, caffeine, clozapine, fluvoxamine, olanzapine, tacrine, theophylline, clorazepate, lidocaine (oral), estradiol, flecanide, imipramine, heparin, insulin, mexiletine, opioids, propranolol, catecholamines, and cortisol. 

Common, non-prescription substances such as caffeine, nicotine, and alcohol often cause sleeping difficulties [41]. In addition, a number of prescribed medications and illegal substances can cause insomnia, depending on factors such as amount used, time of usage, and individual response. Types of drugs that can cause insomnia include energizing antidepressants, anti-hypertensives, bronchodilators, diuretics, beta-blockers, and corticosteroids. 

The combination of caffeine with beta-blockers causes a raised blood pressure (409). 

Initial complaints, which usually diminish with time, include headache, lethargy, and muscle weakness. Nearly half of patients experience a fine hand tremor at some time during lithium treatment. For most people, this initial symptom remits however, for 10 percent of patients, it is a continuing side effect (American Society of Hospital Pharmacists 1993). Often the tremor becomes worse when the individual reaches for something. Sustained tremor, at therapeutic levels, can be managed with reassurance, and by limiting stimulants, such as caffeine, which may exacerbate the tremor. Sometimes this tremor is treated with beta blockers, usually propranolol (In-deral). 

Caffeine causes the release of catecholamines, such as adrenaline, into the blood, which could account for the increases in heart rate and blood pressure that are seen. The blood pressure rise may be exaggerated in the presence of non-selective beta blockers, which block vasodilatation leaving the alpha (vasoconstrictor) effects of adrenaline unopposed. This will also oppose the actions of the beta blockers. 

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