Side-effects may occur following the use of certain drugs, as patients respond differently to medications depending on a variety of factors including age, overall health, gender, ethnicity, and the levels of severity of the illness or disease the patient is fighting. Side-effects may also occur as a result of taking a certain medication in combination with another drug or substance, whether it is a prescription medication, over-the-counter drug, herbal supplement, or food or drink. Beginning treatment with a new medication, ceasing treatment, or adjusting a patient's dosage may also cause a patient to experience unwanted reactions to a medication.
Certain drugs, such as mephenytoin, dilantin and para-aminosalicylic acid, can cause an increased lymphocyte count.
Certain medications, including those containing lactulose or sorbitol, may cause bloating.
Certain medications – such as those prescribed for hypertension, angina, or migraine – can cause feelings of being cold because beta blockers may reduce the circulation in the extremities while increasing blood circulation to the heart.
Some medications can cause non-bloody nipple discharge. The most common culprits are cimetidine (for stomach problems), oral contraceptives, some antidepressant and other drugs for psychological problems, and domperidone (for nausea). Even if you have not noticed any blood, your doctor may ask you to try to squeeze a few drops out, and will test it for microscopic blood.
Hundreds of drugs list dry mouth as a possible side-effect. Antihistamines, decongestants, painkillers, muscle relaxants, and antidepressants are among the drugs that can cause dry mouth.
Certain medicines can damage the liver. Examples include many antibiotics, some types of birth control pill (sex hormones), antipsychotic drugs, and many others.
Almost all medications list dizziness as a possible side-effect. Examples include blood pressure medications, sedatives, tranquilizers, antidepressants, pain relievers, some antibiotics. Diuretics cause dehydration, blood electrolyte changes, heart effects and/or direct side-effects.
It is believed that there may be a link between cluster headaches and some medications such as nitroglycerin (used to treat heart disease.)
Patients demonstrating drug hypersensitivity to aspirin, several nonsterioid antiarthritic agents (Naprosin, Indocin, Motrin), and oral antibiotics, became drug-tolerant when MSM was given within an hour of or concurrently with the sensitizing drug.